WO2009125758A1

WO2009125758A1 - Leather-like sheet having excellent grip performance and artificial leather product using the same

Info

Publication number: WO2009125758A1
Application number: PCT/JP2009/057111
Authority: WO
Inventors: 芦田　哲哉; 延藤　芳樹; 寿山口; 法生牧山; 米田　久夫; 藤本　恭一; 林　宏三
Original assignee: 株式会社クラレ
Priority date: 2008-04-10
Filing date: 2009-04-07
Publication date: 2009-10-15
Also published as: EP2287395A4; JPWO2009125758A1; JP5452477B2; EP2287395A1; EP2287395B1

Abstract

Disclosed is a leather-like sheet which is composed of a fibrous base and unmodified or modified hollow nanosilica particles adhered to at least a part of the fibrous base surface. The leather-like sheet exhibits good grip performance both in dry and wet states. In particular, the leather-like sheet has improved grip performance in a wet state.

Description

Leather-like sheet with excellent grip and artificial leather products using the same

The present invention is a silver-coated leather-like sheet having excellent grip properties when wet, a suede-like leather-like sheet having a unique tactile feeling with excellent grip properties when dry and wet, and an intermediate between nubuck and silver The present invention relates to a leather-like sheet having an appearance (semi-silver tone) and an artificial leather product using the same.

Game balls, gloves, shoe soles, floor materials, etc. are required to show good grip properties when dry, as well as when the surface gets wet with sweat, water, etc. In order to make the surface of a substrate such as metal, plastic, wood, fiber, paper, etc. difficult to slip, a coating composition comprising a polyurethane resin having a hydroxyl group, a liquid rubber having a hydroxyl group, an inorganic or organic filler, and an isocyanate prepolymer It is disclosed that the surface of a base material is coated (Patent Document 1). However, the base material coated with the coating composition becomes slippery when the water absorption amount and the water adhesion amount increase, and the wet grip property is insufficient. Further, Patent Document 1 does not consider any grip property when wet.

In order to improve the water absorption and moisture permeability of synthetic leather, synthetic leather manufactured using a synthetic rubber elastic material mixed with gelatin is disclosed (Patent Document 2). In Patent Document 2, a synthetic rubber elastic material mixed with gelatin is formed into a sheet or film, heated and foamed to form a foamed surface, a part of the surface skin layer is removed, and then the gelatin is removed with hot water. Thus, it is described that the surface has a porous structure. However, the synthetic leather of Patent Document 2 has high surface tack and low wear resistance. Further, Patent Document 2 does not consider any grip property when wet.

In Patent Document 3, microholes having a diameter of 5 to 100 μm communicating with internal pore voids are present at a density of 300 to 10,000 / cm ² , and a penetrant is present inside the microholes. A ball leather-like sheet having an existing porous surface layer is disclosed. It is described that the leather-like sheet has good sweat absorption performance and exhibits non-slip properties by absorbing sweat quickly. However, since the hole diameter is large, it is easy to wear, and when the surface is wet without absorbing sweat, the proposed leather-like sheet becomes slimy and slippery.

Patent Document 4 discloses a game ball covered with synthetic leather. The synthetic leather cover has an uneven outer surface, and a plurality of protrusions and depressions existing between the protrusions are provided on the outer surface. A plurality of holes are provided on the side surface of the protrusion. However, the side surfaces of the protrusions are easily soiled, and if they are soiled, the sweat absorbability is lowered and the grip performance is lowered.

Patent Document 5 discloses a leather-like sheet for a ball having a porous concavo-convex surface in which microholes exist on the surface of the convex portion but substantially no microholes exist on the surface of the concave portion. However, since the surface is porous, it is easy to wear and the inside of the hole is easily stained.

In Patent Document 6, the surface has irregularities, the top of the convex portion has a coating layer made of a polymer elastic body, and the side surface portion of the convex portion has 1000 holes / cm in diameter of 0.5 to 50 μm. ^Two or more existing skin materials for balls are described. However, the concave portion is easily soiled, and the top of the convex portion is covered with the polymer elastic body, so that the touch feeling is inferior.

Patent Document 7 has a porous elastic resin layer formed irregularities on the surface, the leather-like sheet open pores with a diameter of 10 ~ 500 nm on the top surface of the convex portion is present 1000 / cm ² or more Are listed. However, since the surface is porous, the surface wear resistance is inevitably inferior to the nonporous surface. In addition, the proposed technique cannot be applied to a substrate having a smooth surface.

Patent Document 8 discloses a composition for forming a heat insulating layer containing a binder resin, hollow particles, and a solvent or dispersion medium. However, the particle size of the hollow particles is 0.3 to 300 μm, and it is difficult to say that they are nano-sized. In Examples of Patent Document 8, hollow particles having a shell wall of a copolymer such as vinylidene chloride and acrylonitrile and having a particle size of 10 to 30 μm (“Microsphere F-80E” manufactured by Matsumoto Yushi Seiyaku Co., Ltd.) ) Is applied to an acrylic fiber nonwoven fabric to obtain a heat insulating sheet. Patent Document 8 describes nothing about the use of hollow nanosilica particles having a nano-size particle diameter, which will be described later, and improving the wet grip properties of the leather-like sheet by the hollow nanosilica particles. Have not even considered.

A technique for reducing the secondary aggregation property by modifying the surface of the hollow nanosilica particles with various functional groups and improving the reactivity when dispersed in an organic resin or the like is disclosed (Patent Document 9). However, nothing is disclosed in Patent Document 9 regarding specific utilization of surface modification.

Non-slip gloves (Patent Document 10), styrene-isoprene block copolymer or hydrogenated product in which a foamed film of rubber or thermoplastic resin is formed on a fiber glove base material knitted with elastic and non-elastic fibers There is a method (Patent Document 11) in which a resin that imparts non-slip properties, represented by, is applied to the napped surface with a gravure roll with a patterned pattern. Will be lost.

Japanese Patent Publication No. 7-30285 Japanese Unexamined Patent Publication No. 63-152484 JP 2000-328465 A US Pat. No. 6,024,661 JP 2004-300656 A JP 2004-277916 A International Publication WO2008 / 001716 Pamphlet JP 2001-220552 A JP 2007-99607 A JP 2008-0775201 A JP 2001-214376 A

As described above, conventionally known leather-like sheets still have insufficient grip when wet, and improvements have been demanded. Further, conventionally known techniques have attempted to improve water absorption and hygroscopicity by making the surface or the convex portion of the surface porous, thereby improving grip properties when wet. However, wet grip is still insufficient, and surface wear resistance inevitably decreases when the surface is made porous. An object of this invention is to provide the leather-like sheet | seat in which the grip property at the time of wet was improved in such a condition.

In addition, as described above, the conventionally known methods are required for sports gloves and work gloves without losing the elegantly raised feeling of the raised parts, the vivid and dense color tone, and the lighting effect. Grip properties could not be imparted. In particular, the grip performance when wet is not sufficient, not limited to silvered tone and suede tone, and improvement has not been studied. The present invention provides a suede-like leather-like sheet and a semi-silver-like leather-like sheet having an elegant appearance and a soft feel while having the dry and wet grip required for sports gloves and work gloves. The purpose is to do.

As a result of intensive studies to achieve the above-mentioned object, the inventors have heretofore been known that the hollow nanosilica particles that have been known to have excellent anticorrosion properties, heat insulation properties, insulation properties, matting effects, and touch feel when wet. It was found that the effect of improving the grip property is excellent. Furthermore, when wet nano-silica particles (surface-modified particles) surface-modified with at least one compound selected from an isocyanate group-containing compound, an alkyl group-containing compound, an aryl group-containing compound, and a UV functional group-containing compound are grip properties when wet. It was found to be particularly excellent in improving the effect.

Furthermore, the present inventors have found that the grip properties when wet are drastically improved by allowing the hollow nanosilica particles to be present on the napped surface. Furthermore, the surface-modified particles can be uniformly present on the fiber surface with almost no loss of the elegant napping feeling of the raised portions and the lighting effect, and the durability of the grip improving effect by the surface-modified particles is also excellent. I found.

That is, the present invention is a leather-like sheet having a fibrous base material and a silver surface portion covering 10% or more of the surface thereof, and the silver surface portion is composed of a surface layer and a coating layer that is arbitrarily formed. There is provided a leather-like sheet comprising unmodified hollow nanosilica particles and a polymer elastic body having a primary particle size of 50 to 150 nm, or modified hollow nanosilica particles and optionally a polymer elastic body.

Furthermore, the present invention provides a leather having a fiber entangled body composed of a bundle of ultrafine fibers having an average fineness of 0.3 dtex or less and a polymer elastic body existing inside the fiber entangled body and having napped surfaces composed of the ultrafine fibers on the surface. There is provided a leather-like sheet having hollow nanosilica particles having a primary particle diameter of 50 to 150 nm on at least one napped surface.

Furthermore, the present invention provides an artificial leather product in which at least a part of the surface is formed of the leather-like sheet.

The leather-like sheet of the present invention has a silver part on at least a part of its surface. The silver surface portion is composed of a surface layer and an arbitrary coating layer positioned below the surface layer, and the surface layer is composed of unmodified hollow nanosilica particles and a polymer elastic body, or modified hollow nanosilica particles and an arbitrary polymer elastic body. Since the surface layer contains unmodified or modified hollow nanosilica particles, the leather-like sheet of the present invention has good grip properties not only when dry but also when wet, even if the surface is not porous. Further, since the surface does not need to be porous, the surface strength such as surface wear resistance is excellent.

In another embodiment, the leather-like sheet of the present invention has an elegant napping feeling and color tone peculiar to a suede tone because the hollow nanosilica particles adhere to the surface napped fibers and the fiber bundle surface without a binder. It has a good grip and a unique tactile sensation when dry and wet while having a soft texture without loss. The length of the surface raised fibers of the leather-like sheet is further shortened, and further, the napped-like leather-like sheet is produced in terms of appearance and feel by applying a polymer elastic body or the like and partially laying the raised fibers. It is also possible.

In yet another embodiment, the leather-like sheet of the present invention is a semi-silver leather-like sheet in which a covering portion and a napped portion are mixed. Since hollow nanosilica particles are present in the napped portion, the semi-silver leather-like sheet of the present invention maintains a high-grade appearance without impairing the lighting effect of the napped portion, and is good not only when dry but also when wet Has grip and unique touch.

It is a cross-sectional schematic diagram which shows an example (a linear part is a convex part) of the uneven | corrugated | grooved part arbitrarily formed in the leather-like sheet | seat of this invention. It is a cross-sectional schematic diagram which shows an example (a linear part is a convex part of a secondary uneven part) of the secondary uneven part arbitrarily formed in the leather-like sheet | seat of this invention. It is a cross-sectional schematic diagram explaining the depth (distance: D) of a recessed part. It is a cross-sectional schematic diagram explaining the boundary (B) of a recessed part and plane part of a semicircular cross section. It is a cross-sectional schematic diagram explaining the boundary (B) of a recessed part of a cross-sectional trapezoid shape, and a plane part. It is a plane schematic diagram which shows an example (the filling part is a recessed part of a secondary uneven part) of a secondary uneven part.

(1) Toned leather-like sheet with silver The leather-like sheet of the present invention has a fibrous base material and a silver part covering 10% or more of the surface thereof. The silver part consists of a surface layer and an optional coating layer. In one embodiment of the present invention, the surface layer includes hollow nanosilica particles (unmodified surface) and a polymer elastic body. In another embodiment, the surface layer is hollow nanosilica particles surface-modified with at least one compound selected from a compound having an isocyanate group, a compound having an alkyl group, a compound having an aryl group, and a compound having a UV functional group ( Surface-modified particles) and polymer elastic bodies. In yet another embodiment, the surface layer includes surface-modified particles but does not include a polymer elastic body.

As the fibrous base material, a knitted fabric, a nonwoven fabric or a fiber entangled body (three-dimensional entangled nonwoven fabric) is preferably used. The fibrous base material is preferably impregnated with a polymer elastic body. A fiber entangled body impregnated with a polymer elastic body is more preferably used as the fibrous base material. In particular, it is preferable to contain a polymer elastic body in the fiber entangled body because physical properties such as strength of the fibrous base material are improved and a natural leather-like texture is easily obtained. The polymer elastic body to be contained in the fiber entangled body is more preferably a sponge (porous). When it is sponge-like, the texture of the silver-finished leather-like sheet and the later-described semi-silvered and suede-like leather-like sheets are more flexible and have a feeling of swelling, and cushioning while maintaining lightness. Can be granted.

The fibers constituting the knitted fabric, the nonwoven fabric and the fiber entangled body are selected from conventionally known natural fibers, synthetic fibers and semi-synthetic fibers. Industrially known cellulose fibers, acrylic fibers, polyester fibers, polyamide fibers and the like are preferably used alone or in admixture of two or more in view of quality stability and price. In the present invention, although not particularly limited, a soft texture closer to that of natural leather can be realized, and in the case of semi-silver-like and suede-like leather-like sheets, the fiber surface on which hollow nanosilica particles can exist is extremely wide. Therefore, an ultrafine fiber is preferable. The average fineness of the ultrafine fibers is preferably 0.3 dtex or less, more preferably 0.0001 to 0.3 dtex, and still more preferably 0.0001 to 0.1 dtex.

As a method for obtaining such an ultrafine fiber, (a) a method of directly spinning an ultrafine fiber having a target average fineness, and (b) a fine fiber-generating fiber that is once thicker than the target fineness is spun, and then the target And a method of transforming into ultrafine fibers having an average fineness of When the basis weight of the fibrous base material exceeds 200 g / m ² , it is often difficult to continuously produce a fibrous base material composed of ultrafine fibers in terms of elongation due to tension and thickness reduction. In the latter half of the production process, the method (b) of transforming the ultrafine fiber-generating fiber into the ultrafine fiber is preferable.

In the method (b), two or more types of thermoplastic polymers that are not compatible are combined or spun to obtain ultrafine fiber-generating fibers, and at least one polymer component is extracted from the ultrafine fiber-generating fibers. It is common to transform into ultrafine fibers by removing or decomposing, or by separating and peeling the polymer at the interface of the polymer components. Examples of the ultrafine fiber-generating fiber containing a removable polymer component include sea-island fiber and multilayer laminated fiber. In the case of sea island type fibers, the sea component polymer is extracted or removed by decomposition, and in the case of multilayer laminated type fibers, at least one of the laminated polymer components is extracted and removed or decomposed to remove island components (non- An ultrafine fiber bundle composed of the removed polymer component) is obtained. The solvent used for extraction or decomposition / removal may be any solvent that does not dissolve the island component (non-removed polymer component) but dissolves the sea component polymer, and practically includes water and toluene. In addition, examples of the ultrafine fiber-generating fiber that is separated at the interface of the polymer component include petal-like laminated fiber and multi-layer laminated fiber, and between different polymer components laminated by physical treatment or chemical treatment. Ultrafine fiber bundles can be obtained by peeling each other at the interface.

The island component polymer of the sea-island fiber or multilayer laminated fiber is a polymer that can be melt-spun and has sufficient fiber properties such as strength, and has a higher melt viscosity than the sea-component polymer and a surface tension under the spinning conditions. Larger polymers are preferred. Examples of such island component polymers include polyamides such as nylon-6, nylon-66, nylon-610, nylon-612, and copolymers based on these, or polyethylene terephthalate, polypropylene terephthalate, polytrimethylene terephthalate. Polyesters such as polybutylene terephthalate and copolymers mainly composed thereof are preferably used.

As sea component polymer of sea island type fiber or multilayer laminated fiber, melt viscosity is lower than island component polymer, solubility in solvent or decomposability by decomposing agent is larger than island component polymer, polyethylene, modified polyethylene, polypropylene, Polystyrene, modified polystyrene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, styrene-ethylene copolymer, styrene-acrylic copolymer, modified polyester, polyvinyl alcohol resin and the like are preferably used. When using sea-island type fibers, ultrafine fibers can be obtained by extracting and removing the sea component polymer with an organic solvent, but water or an aqueous solution set at a predetermined temperature and a predetermined pH can be obtained without using an organic solvent. It is preferable to use water-soluble thermoplastic polyvinyl alcohol (water-soluble PVA) as the sea component polymer in that it can be used to obtain ultrafine fibers.

The water-soluble PVA has a viscosity average polymerization degree (hereinafter simply referred to as a polymerization degree) of preferably 200 to 500, more preferably 230 to 470, and further preferably 250 to 450. When the degree of polymerization is 200 or more, the melt viscosity is moderate and it is easy to combine with the island component polymer. When the degree of polymerization is 500 or less, it is possible to avoid a problem that it is difficult to discharge the resin from the spinning nozzle because the melt viscosity is too high. By using so-called low polymerization degree PVA having a polymerization degree of 500 or less, there is also an advantage that the dissolution rate is increased when dissolving with hot water. The degree of polymerization (P) of water-soluble PVA is measured according to JIS-K6726. That is, after re-saponifying and purifying water-soluble PVA, it is obtained from the intrinsic viscosity [η] measured in water at 30 ° C. by the following equation.
P = ([η] 10 ³ /8.29) ^{(1 / 0.62)}

The saponification degree of the water-soluble PVA is preferably 90 to 99.99 mol%, more preferably 93 to 99.98 mol%, further preferably 94 to 99.97 mol%, and particularly preferably 96 to 99.96 mol%. . When the degree of saponification is 90 mol% or more, thermal stability is good, satisfactory melt spinning can be performed without thermal decomposition or gelation, and biodegradability is also good. Further, the water-solubility is not lowered by the copolymerization monomer described later, and it becomes easy to make it ultrafine. Water-soluble PVA having a degree of saponification of greater than 99.99 mol% is difficult to produce stably.

The melting point (Tm) of the water-soluble PVA is preferably 160 to 230 ° C, more preferably 170 to 227 ° C, further preferably 175 to 224 ° C, and particularly preferably 180 to 220 ° C. When the melting point is 160 ° C. or higher, the crystallinity is not lowered and the fiber strength is not lowered, and it is also possible to prevent the fiber from becoming difficult due to poor thermal stability. When the melting point is 230 ° C. or less, melt spinning can be performed at a temperature lower than the decomposition temperature of PVA, and sea-island long fibers can be stably produced.

Water-soluble PVA can be obtained by saponifying a resin mainly containing vinyl ester units. Vinyl compound monomers for forming vinyl ester units include vinyl formate, vinyl acetate, vinyl propionate, vinyl valenate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl benzoate, vinyl pivalate and Examples include vinyl versatate, and among these, vinyl acetate is preferable from the viewpoint of easily obtaining water-soluble PVA.

The water-soluble PVA may be a homo-PVA or a modified PVA into which a copolymer unit is introduced, but it is preferable to use a modified PVA from the viewpoint of melt spinnability, water-solubility and fiber properties. Examples of the comonomer include α-olefins having 4 or less carbon atoms such as ethylene, propylene, 1-butene, and isobutene, methyl vinyl ether, and ethyl vinyl ether from the viewpoints of copolymerizability, melt spinnability, and water solubility of the fiber. Vinyl ethers such as n-propyl vinyl ether, isopropyl vinyl ether and n-butyl vinyl ether are preferred. The amount of units derived from α-olefins having 4 or less carbon atoms and / or vinyl ethers is preferably 1 to 20 mol%, more preferably 4 to 15 mol%, and more preferably 6 to 13 mol% of the modified PVA constituent unit. Further preferred. Further, when the comonomer is ethylene, the fiber properties are improved, and therefore modified PVA containing ethylene units preferably in an amount of 4 to 15 mol%, more preferably 6 to 13 mol% is preferable.

Water-soluble PVA is produced by a known method such as a bulk polymerization method, a solution polymerization method, a suspension polymerization method, or an emulsion polymerization method. Among these, a bulk polymerization method or a solution polymerization method in which polymerization is performed without solvent or in a solvent such as alcohol is preferable. Examples of the solution polymerization solvent include lower alcohols such as methyl alcohol, ethyl alcohol, and propyl alcohol. Examples of the initiator used for copolymerization include a, a′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethyl-valeronitrile), benzoyl peroxide, and n-propyl peroxycarbonate. And known initiators such as azo initiators or peroxide initiators. The polymerization temperature is not particularly limited, but a range of 0 to 150 ° C. is appropriate.

The sea-island volume ratio (sea / island) of the ultrafine fiber-generating fiber suitable for generating ultrafine fibers having an average fineness of 0.3 dtex or less, that is, sea-island type fiber is preferably 15/85 to 70/30, and 30/70 ~ 70/30 is more preferable, 30/70 to 60/40 is further more preferable, and 40/60 to 60/40 is particularly preferable. If the sea component is 15% or more, the amount of the component dissolved or decomposed and removed with a solvent or a decomposing agent is sufficient, so that the flexibility of the obtained leather-like sheet can be sufficiently expressed. Therefore, measures such as excessive use of treatment agents such as softeners are not required. Use of an excessive amount of the treatment agent is not preferable because it causes problems such as deterioration in mechanical properties such as tear strength, influence on other treatment agents, influence on touch, and deterioration in durability. Moreover, if the sea component is 70% or less, the absolute amount of fibers composed of island components after dissolution or decomposition is sufficient, and thus the obtained leather-like sheet has sufficient mechanical properties. In addition, since there are not too many components to dissolve or decompose and remove, there are no problems such as quality irregularities due to defective removal and processing of removed components generated in large quantities, and productivity viewpoints such as production speed and cost. It is also suitable from the industrial viewpoint. The ultrafine fiber generation type fiber is a method of spinning the above-mentioned sea component polymer and island component polymer by mixing them at a predetermined ratio in advance at the time of polymer melting and then extruding them to a composite fiber spinning die (mixed spinning method). Alternatively, the polymer can be obtained by any method of spinning (composite spinning method) by extruding and feeding each polymer from a different melt system to a composite fiber spinning die at a predetermined ratio. The spinning temperature (die temperature) is a temperature determined appropriately depending on the combination of the island component polymer and the sea component polymer to be used. In the polymer combination suitable for the present invention, it is usually selected from the range of about 180 to 350 ° C. . The average fineness of the entangled nonwoven fabric of the ultrafine fiber generating fiber is 1 to 10 dtex. The density of the entangled nonwoven fabric and the strength properties as a sheet, the texture and swelling after impregnating the resin described later, etc. This is preferable. In the cross section of the ultrafine fiber-generating fiber, the number of island component polymers dispersed in the sea component polymer (number of islands) is preferably 10 to 10,000, more preferably 150 to 10,000 in the mixed spinning method. In the composite spinning method, the number is preferably 10 to 1,000. Within this range, the cross-sectional shape of the fiber during melt spinning, the stability of the continuous spinning state (spinning property), the stretching stability of the composite fiber, the strength properties of the composite fiber, the formability of ultrafine fibers by sea component extraction, etc. are good. It is.

In the production of conventional artificial leather and the like, a fiber web was produced from staples obtained by cutting ultrafine fiber-generating long fibers into an arbitrary fiber length, but in the present invention, a sea island spun by a spunbond method or the like. You may make it a fiber web, without cutting a type | mold long fiber (ultrafine fiber generation type | mold long fiber). In the present invention, the fiber web production method is not particularly limited, and the fiber web is produced by a conventionally known method such as a card method, a papermaking method, a spunbond method, a meltblown method using an ultrafine fiber generating short fiber or an ultrafine fiber generating long fiber. Manufacturing.

Next, the fiber web is entangled to produce a fiber entangled body (three-dimensional entangled nonwoven fabric). As the entanglement method, conventionally known methods such as a needle punch method and a spunlace method can be used alone or in combination. A particularly preferred method is to draw ultrafine fiber-generated long fibers obtained by spinning to about 1.5 to 5 times, then apply mechanical crimping and cut to about 3 to 7 cm length to obtain short fibers. Later, this is defibrated with a card to form a fibrous web of a desired density through a webber, the resulting fibrous web is laminated to a desired weight, and then a needle with one or more barbs is used In this method, the fibers are entangled in the thickness direction by needle punching at about 300 to 4000 punches / cm ² . The basis weight of the fiber entangled body may be adjusted according to the basis weight of the product, but it is preferably 200 to 1000 g / m ² from the viewpoint of the subsequent process passability and workability.

Subsequently, the obtained fiber entangled body is subjected to a known method such as a dip nip method, a knife coating method, a bar coating method, a roll coating method, a spray coating method, or the like as necessary. Next, the polymer elastic body is solidified by a dry method or a wet method. By selecting the coagulation conditions, the effect as described above can be obtained by coagulating the elastic polymer so as to form a large number of voids in a sponge shape. As the polymer that can be used, any known polymer generally used in the production of leather-like sheets can be used. For example, polyurethane-based resins, polyester-based elastomers, rubber-based polymers can be used. Suitable examples include resins, polyvinyl chloride resins, polyacrylic acid resins, polyamino acid resins, silicon resins, and their modified products, copolymers, or mixtures.

In the case of impregnating a fiber entangled body with a polymer elastic body, an aqueous dispersion or an organic solvent solution is preferable. As a method of solidifying the impregnated polymer elastic body, when an aqueous dispersion is used, a method of gelling or solidifying mainly by a dry method (50 to 150 ° C.) can be cited, In the case where a solvent solution is used, the dry method or the wet method may be used. By appropriately selecting the coagulation conditions, the polymer elastic body can be coagulated in a porous state. As the porous solidification method in the present invention, solidification by a wet method (wet solidification method) is suitable. In the wet coagulation method, a fiber entangled body impregnated with an organic solvent solution is immersed in a treatment bath containing a poor solvent for a polymer elastic body to solidify the polymer elastic body into a porous state. Water is preferably used as the poor solvent for the polymer elastic body. For example, when polyurethane is used as the polymer elastic body, a treatment bath in which a good solvent for the polymer elastic body such as dimethylformamide (DMF) is mixed with water. Is preferably used because it is possible to control the solidification state, that is, the size, number, shape, etc., of the formed pores by appropriately setting the mixing ratio. When using an aqueous dispersion, adding a heat-sensitive gelling agent allows solidification more uniformly in the thickness direction by combining a dry method or a method such as steaming or far-infrared heating. . When an organic solvent is used, more uniform pores can be obtained by using a coagulation regulator in combination. Examples of the organic solvent include dimethylformamide, dimethylacetamide, dimethyl sulfoxide and the like. A fiber entangled body, especially a polymer polymer impregnated in a three-dimensional entangled non-woven fabric, is solidified in a porous form to create a texture similar to that of natural leather, especially game ball materials, gloves materials, A leather-like sheet having various physical properties suitable for an insole material, a sandal ceiling material, a vehicle seat surface material, and the like can be obtained.

In the present invention, a polyurethane-based resin is preferably used as the polymer elastic body from the viewpoint of the texture of the composite (fibrous substrate) composed of the ultrafine fiber entangled body and the polymer elastic body, and the balance of physical properties. Examples of the polyurethane resin include various kinds obtained by reacting at least one polymer diol having an average molecular weight of 500 to 3000, at least one organic diisocyanate, and at least one chain extender in a predetermined molar ratio. Of polyurethane. Examples of the polymer diol include polyester diol, polyether diol, polyester ether diol, polylactone diol, and polycarbonate diol. Examples of organic diisocyanates include aromatic and alicyclic aromatic groups such as tolylene diisocyanate, xylylene diisocyanate, phenylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate. And aliphatic organic diisocyanates. Examples of the chain extender include low molecular compounds having at least two active hydrogen atoms such as diol, diamine, hydroxyamine, hydrazine, hydrazide. If necessary, the polyurethane may be a mixture of a plurality of types of polyurethane, or a polymer composition obtained by adding a polymer such as synthetic rubber, polyester elastomer, or polyvinyl chloride.

When using the above-mentioned ultrafine fiber generating fiber, after impregnating and solidifying the polymer elastic body solution or dispersion, or before impregnating and solidifying, ultrafine fiber generation treatment is performed. Transform fibers into ultrafine fiber bundles. When the ultrafine fiber treatment is performed after solidifying the polymer elastic body, particularly if it is a sea-island type fiber, the sea component polymer is removed and a void is generated between the ultrafine fiber bundle and the polymer elastic body, This method is preferably employed in the present invention because the restraint of the ultrafine fiber bundle by the polymer elastic body becomes weak and the texture of the resulting leather-like sheet becomes softer. On the other hand, when the ultrafine fiber treatment is performed before impregnating and solidifying the polymer elastic body, the ultrafine fiber bundle is strongly restrained by the polymer elastic body, and the texture of the resulting leather-like sheet tends to be harder There is. However, when the ratio of the polymer elastic body in the fiber entangled body is reduced, it is possible to suppress the tendency to become hard enough, and when the fiber ratio is higher and a solid texture with a sense of fulfillment is intended. Is a preferred method. The average fineness of the fiber bundle of ultrafine fibers is preferably 1 to 10 dtex.

The thickness of the fibrous base material used in the present invention depends on the intended use, for example, the surface material of a game ball, depending on the type of game ball, the required physical properties, or the texture preferred by the player. Although it can be arbitrarily selected and is not particularly limited, it is preferably 0.4 to 3.0 mm. If the thickness of the fibrous base material is 0.4 mm or more, the tensile strength, tear strength, or resistance required for ball materials, cover materials for grips such as rackets, handles, handrails, and sports gloves materials, etc. Minimum required mechanical properties such as wear can be ensured. On the other hand, if the thickness of the fibrous base material is 3.0 mm or less, the product using the leather-like sheet can be prevented from becoming too heavy.
If it is a material for gloves, it can be arbitrarily selected according to the type of gloves, the required physical properties, or the texture that the player prefers, and although it is not particularly limited, it generally fits the hand Since it is easy to obtain a feeling, 0.2 to 1.2 mm is preferable, and 0.3 to 0.9 mm is more preferable.
In the case of materials for insoles, insoles, and sandals, the material varies depending on the application, purpose and structure of the shoe itself, and the material to be combined. From the point, 0.3 to 1.5 mm is preferable, and 0.5 to 1.3 mm is more preferable.
In the case of surface materials such as sofas and vehicle seats, in-plane strength and surface strength are particularly important, and it varies depending on the room where the sofa is installed, the concept of the vehicle itself, and the user. Is preferably 0.5 to 2.0 mm, more preferably 0.7 to 1.8 mm.

Further, the mass ratio between the ultrafine fibers and the polymer elastic body in the fibrous base material may be appropriately selected according to the required physical properties and texture, and is not an essential feature for obtaining the effects of the present invention. Usually, it is 35/65 to 90/10. For example, when used for a game ball material or a glove material, the mass ratio is preferably 35/65 to 65/35, more preferably 40/60 to 60/40 (impregnated and solidified with a polymer elastic body). Or in the case of 65/35 to 95/5, more preferably 60/40 to 90/10 (when the polymer elastic material is impregnated and solidified before solidification). In particular, when obtaining a semi-silver leather-like sheet, it is preferably 50/50 to 80/20, more preferably 60/40 to 70/30.

A covering layer (not including unmodified or modified hollow nanosilica particles) made of a polymer elastic body may be formed on the surface of the fibrous base material as a layer constituting a part of the silver surface portion. Various methods can be adopted as a method of coating the surface of the fibrous base material with the polymer elastic body. For example, a polymer elastic dispersion, solution, or melt is continuously applied to the substrate surface in an amount regulated by a certain clearance set between the fiber substrate surface and a knife, bar, roll, etc. And solidified into a film by a dry method. In the present invention, even when the coating layer is nonporous, the wet grip properties can be sufficiently improved by the unmodified or modified hollow nanosilica particles. Therefore, the coating layer does not necessarily need to be porous, but may be solidified into a porous state by a wet method if necessary. The methods of dry solidification and wet solidification are as described above. When the fibrous base material is composed of a fiber entangled body and a polymer elastic body, a method of completing coagulation of the polymer elastic body to be impregnated into the fiber base material and coagulation of the polymer elastic body forming the coating layer at the same time. Employment is preferable because drying after solidification can be completed in one time, and in the obtained leather-like sheet, a sense of unity between the fibrous base material and the coating layer is easily obtained.

As another method for forming the coating layer on the surface of the fibrous base material, a predetermined amount of a polymer elastic dispersion or solution is once applied to a transfer release sheet such as a film or release paper, and the same as described above. After the polymer elastic body is solidified into a film or porous state by the method and dried, the polymer elastic body is adhered to the fibrous base material via an adhesive, or a treatment liquid containing a solvent for the polymer elastic body For example, a method of bonding by re-dissolution and integrating them, and then peeling the release transfer sheet. Similarly, after applying a predetermined amount of the dispersion or solution of the polymer elastic body to the transfer release sheet and then coagulating it, or pasting it on the fiber base material in the middle and coagulating it, the coating layer and the fiber base A method of integrating the material can also be adopted.

The polymer elastic body forming the coating layer is preferably a resin having a certain degree of grip rather than a slippery resin. For example, synthetic rubber, polyester elastomer, polyvinyl chloride resin, polyurethane resin, etc. can be used. It is. Among these, from the viewpoint of balance such as elasticity, softness, and abrasion resistance, a polyurethane-based resin is preferably used in the same manner as the polymer elastic body contained in the fiber entangled body.

The polyurethane-based resin for forming the coating layer is selected from polyurethane-based resins to be included in the fiber entangled body. If necessary, a mixture of a plurality of types of polyurethane-based resins may be used, and a polymer composition mainly composed of polyurethane may be used by adding a polymer such as synthetic rubber, polyester elastomer, or polyvinyl chloride. You can also. From the standpoint of hydrolysis resistance and elasticity, a polyurethane resin in which the polymer diol component is a polyether polymer diol such as polytetramethylene glycol is preferred.

In the polymer elastic body solution or dispersion for forming the coating layer, additives such as a colorant, a light fastness agent, and a dispersant are appropriately added depending on the purpose, either alone or in combination. As other additives, in order to control the porous shape, in addition to the foaming agent in the case of dry foaming, a coagulation regulator in the case of wet coagulation is selected as necessary, alone or several Combinations of seeds may be added.

The thickness of the covering layer can be arbitrarily selected according to the intended use, for example, the surface material of a game ball, depending on the type of ball, the required physical properties, or the texture preferred by the player, etc. However, it is preferably 0.03 to 0.5 mm, more preferably 0.1 to 0.3 mm. If the thickness of the coating layer is 0.03mm or more, it can be used as a cover material for grips such as various rackets, handles, and handrails as well as game ball materials. It is possible to secure the minimum required mechanical properties such as properties. On the other hand, if the thickness of the coating layer is 0.5 mm or less, products such as game balls, rackets, and handles can be prevented from becoming excessively heavy.

Since it is important that the silver part covers 10% or more of the surface of the fibrous base material in terms of maintaining grip, it is preferable that the coating layer also covers 10% or more of the surface of the fibrous base material. If the silver surface portion is less than 10% of the surface of the fibrous base material, it is difficult to ensure sufficient grip properties both when dry and when wet. Moreover, what is necessary is just to apply | coat by the well-known method regarding the method of making a coating layer 10% or more. In addition, the silver surface part said here 10% or more of the surface of a fiber base material means that the surface of a leather-like sheet is observed and the area of the said surface layer is 10% or more of the surface area of a fiber base material. To do.

Next, a dispersion containing unmodified hollow nanosilica particles, a polymer elastic body, and a solvent on the surface of the fibrous base material or, if a coating layer is formed, on the surface of the coating layer or the surface of the coating layer and the exposed surface of the fibrous base material A liquid or a dispersion containing modified hollow nanosilica particles, a solvent and an arbitrary polymer elastic body is applied and dried to form a surface layer of the silver surface portion. As a method for coating a desired portion of the surface of the fibrous base material with the silver surface portion, various conventionally known methods can be employed alone or in combination. For example, the dispersion for forming the surface layer is excessively supplied onto the fibrous base material, and the coating amount is adjusted to a necessary amount by a clearance between the fibrous base material and a coater such as a knife, bar, roll, Examples thereof include a method of solidifying and solidifying by a dry method or a wet method. In the case of using a gravure roll coater, comma coater, spray coater, etc., a method of applying a pre-weighed amount of coating liquid to the surface of the substrate and solidifying and solidifying the substrate by the dry method or wet method is also mentioned. It is done. In the present invention, even when the silver surface portion is nonporous, the wet grip properties can be sufficiently improved by the unmodified or modified hollow nanosilica particles. Therefore, the silver surface portion does not necessarily need to be porous, but may be solidified into a porous shape by a wet method as necessary. When the fibrous base material is a composite comprising a fiber entangled body and a polymer elastic body, the solidification of the polymer elastic body impregnated into the fibrous base material and the solidification of the polymer elastic body forming the silver surface portion are simultaneously performed. When the completion method is adopted, drying after solidification can be completed in one time, and in the obtained leather-like sheet, it is easy to obtain a sense of unity between the fibrous base material and the silver surface portion. This is a preferable method.

When the dispersion contains a polymer elastic body, as another method for forming a silver surface portion on the surface of the fibrous base material, the dispersion is post-measured on a transfer release sheet such as a film or release paper with the knife coater or the like. While applying a predetermined amount, the polymer elastic body is solidified into a film or porous state by the same dry method or wet method as described above, and then dried and solidified. A method of adhering to a substrate through an adhesive, a method of adhering to a base material by adhering with a polymer elastic material re-dissolved using a treatment liquid containing a solvent for the polymer elastic material, and peeling Examples include a method of attaching to the substrate before the coating solution on the transfer sheet solidifies and solidifies, and then the release transfer sheet is peeled off to form the uneven pattern or mirror surface state formed on the release transfer sheet surface. And get the silver part with the transferred That (transfer peeling method).

The polymer elastic body forming the silver surface is preferably a resin having a certain degree of grip rather than a slippery resin. For example, synthetic rubber, polyester elastomer, polyvinyl chloride resin, polyurethane resin, etc. can be used. It is. Among these, from the viewpoint of balance such as elasticity, softness, and abrasion resistance, a polyurethane-based resin is preferably used in the same manner as the polymer elastic body contained in the fiber entangled body.

The polyurethane resin for forming the silver surface portion is selected from the same resins as the polyurethane resin to be contained in the fiber entangled body. If necessary, a mixture of a plurality of types of polyurethane-based resins may be used, and a polymer composition mainly composed of polyurethane may be used by adding a polymer such as synthetic rubber, polyester elastomer, or polyvinyl chloride. You can also. From the standpoint of hydrolysis resistance and elasticity, a polyurethane resin in which the polymer diol component is a polyether polymer diol such as polytetramethylene glycol is preferred.

In the dispersion of unmodified or modified hollow nanosilica particles and polymer elastic body to be coated on the fibrous base material, additives such as a colorant, a light-proofing agent, and a dispersant may be used alone or in combination of a plurality of types. It is appropriately added depending on the case. As other additives, in order to control the porous shape, in addition to the foaming agent in the case of dry foaming, a coagulation regulator in the case of wet coagulation is selected as necessary, alone or several Combinations of seeds may be added.

As a method of forming a silver surface portion on the surface of a fibrous base material, in addition to the above-described method of applying a dispersion containing unmodified or modified hollow nanosilica particles and a polymer elastic body, and a transfer peeling method using the dispersion , After forming a coating layer made of a polymer elastic body (not including unmodified or modified hollow nanosilica particles), another coating solution containing unmodified or modified hollow nanosilica particles and a polymer elastic body is applied to the surface of the coating layer. The method of apply | coating and further forming the surface layer which consists of an unmodified or modified hollow nano silica particle and a polymeric elastic body is mentioned. In the latter case, a surface layer containing unmodified or modified hollow nanosilica particles is formed only on the outermost surface portion of the silver surface portion.

When the layer constituting the silver part is only a layer (surface layer) containing unmodified or modified hollow nanosilica particles and a polymer elastic body, the thickness of the silver part depends on the intended use, for example, the surface material of the game ball. If there is, it can be arbitrarily selected according to the type of ball, the required physical properties, or the texture that the player likes, and is not particularly limited, but is preferably 0.05 to 0.5 mm, More preferably, it is 0.1 to 0.3 mm. If the thickness of the silver part is 0.05mm or more, it is necessary to have the minimum wear resistance as well as the material for game balls, as well as the cover material for grips such as various rackets, handles, and handrails. It is preferable because mechanical properties can be secured. On the other hand, if the thickness of the silver surface portion is 0.5 mm or less, products such as game balls, rackets, and handles can be prevented from becoming excessively heavy.

When the silver surface portion is composed of a surface layer containing a non-modified or modified hollow nanosilica particle and a polymer elastic body and a coating layer, the thickness of the surface layer is preferably 0.001 to 0.1 mm, more preferably 0. The thickness of the coating layer is preferably 0.03 to 0.5 mm, more preferably 0.08 to 0.3 mm. The total thickness of the surface layer and the coating layer is preferably 0.05 to 0.5 mm, more preferably 0.1 to 0.3 mm.

When the silver surface portion is composed of a surface layer (not including a polymer elastic body) containing unmodified or modified hollow nanosilica particles and a coating layer, the thickness of the surface layer is preferably 0.00003 to 0.008 mm, more The thickness is preferably 0.00005 to 0.005 mm, and the total thickness of the surface layer and the coating layer is preferably 0.05 to 0.5 mm, more preferably 0.1 to 0.3 mm.

In addition, as a factor that determines the preferred thickness of the silver surface portion, in addition to the absolute requirements that come from the above-mentioned use, the balance with the thickness of the fibrous base material in the thickness of the entire leather-like sheet is also important, Empirically, the thickness ratio between the silver surface portion and the fibrous base material is preferably in the range of 0.01: 99.9 to 60:40. If the ratio of the silver part is greater than 0.01, the presence of the silver part is sufficiently felt in the texture, and if it is less than 60, a so-called rubber-like leather-like sheet mainly composed of the silver part in the texture is obtained. Can be avoided.

Concavities and convexities may be formed on the surface layer and the coating layer of the silver surface layer as necessary. A preferable concavo-convex shape and a forming method thereof will be described later. Moreover, you may color a silver surface part. The coloring process can be performed either before or after forming the unevenness described later. For example, when forming irregularities with an embossing roll, either before or after the embossing treatment is possible, but the embossing treatment is often performed by heating, and the surface layer and the coating layer may change color. It is preferable to perform a coloring treatment for preventing discoloration by heating before embossing. As the colorant, a pigment is the best from the viewpoint of heat resistance, light resistance, and friction fastness. As a method for treating the colorant, there are a gravure method, a dyeing method, a reverse coating method, a direct coating method, and the like, but the gravure method is optimal in consideration of productivity and cost.

When a coating layer is formed on a part of or the entire surface of the fibrous base material, unmodified or modified hollow nanosilica particles, polymer elastic bodies (binders) on the surface of the coating layer or the exposed surface of the coating layer and the fibrous base material ) And a solvent-containing dispersion, and then dried to form a surface layer of the silver surface portion.

Hollow nanosilica particles are silica particles having a balloon structure (hollow shape) having a dense silica shell and excellent nano-sized dispersibility. For example, the methods described in JP-A-2005-263550 and JP-A-2006-256922 Manufactured by. The primary particle size of the hollow nanosilica particles is 50 to 150 nm, the thickness of the silica shell (transmission electron microscope (TEM)) is 5 to 15 nm, the specific surface area (BET method) is 150 to 300 m ² / g, and the pore volume (mercury) (Press-in method) is 9000 to 13000 mm ³ / g, bulk density is 0.03 to 0.07 g / mL, and shell wall pores are 5 nm or less (below the direct observation limit by TEM), preferably 2 nm or less (BET Law).

As described above, the hollow nanosilica particles may be surface-modified particles whose surfaces are modified with a surface modifier. For example, according to the method of Patent Document 9, a surface modifying particle can be obtained by adding a surface modifying agent to a hollow nanosilica particle via a hydroxyl group (—OH) present on the surface and coating the surface with the surface modifying agent. . By surface modification, aggregation of primary particles can be prevented, so that dispersibility of particles in the dispersion is improved. Further, since the active group of the polymer elastic body in the fibrous base material and / or coating layer reacts with the isocyanate group or the like of the surface modifier, the polymer elastic body (binder) is added to the dispersion for forming the surface layer. Even if it is not used, the adhesiveness of the surface layer and fibrous base material and / or coating layer which are obtained is favorable.

Surface modifiers include isocyanate compounds, amine compounds, vinyl compounds, epoxy compounds, methacryloxy compounds, acrylic compounds, imide compounds, compounds having an alkyl group, compounds having an aryl group, and UV functional groups. Or the like. The UV functional group is a functional group that reacts with ultraviolet rays (UV) such as a vinyl group, a styryl group, and an acrylic group. Among them, a compound having at least one group selected from an isocyanate group, an alkyl group, an aryl group, and a UV functional group is preferable. Uniform dispersibility on the surface of the leather-like sheet, durability of the adhesion state, and a fibrous base material Isocyanate compounds are particularly preferred because they are excellent in reactivity with the polyamide resin, polyester resin and polyurethane resin to be formed and are easily available. As described in Patent Document 9, the surface-modified particles are invented for the purpose of improving the dispersibility of the hollow nanosilica particles, but in the present invention, the obtained grip performance is exhibited permanently. It contributes to. A commercially available product of surface-modified particles is available from Grandex Co., Ltd. as Nanotouch (registered trademark).

The polymer elastic body optionally contained in the dispersion for forming the surface layer is selected from polymer elastic bodies for inclusion in the fibrous base material, and the above-described polyurethane-based resin is preferably used. Examples of the solvent for the dispersion include hydrocarbons such as n-hexane and cyclohexanone, aliphatic alcohols such as methanol, ethanol and propanol, aromatic hydrocarbons such as toluene and xylene, ketones such as acetone, and dimethylformamide. And amides. These solvents may be used alone or in combination of two or more. If the modifying group does not react with water, it can be dispersed in water.

The solid content (total of unmodified or modified hollow nanosilica particles and polymer elastic body) in the dispersion for forming the surface layer is preferably 5 to 20% by mass. When the polymer elastic body is used, the content of unmodified or modified hollow nanosilica particles is preferably 5 to 15 parts by mass with respect to 100 parts by mass of the polymer elastic body.

When the hollow nanosilica particles are unmodified particles, the amount of the dispersion applied to the surface of the fibrous base material and / or the coating layer after drying (after removal of the solvent) (unmodified hollow nanosilica particles) is 0.02 to 0. it is preferred to coat such that .8g / m ^2. When the hollow nanosilica particles are modified particles, the coating amount (surface modified particles) after drying (after solvent removal) is preferably 0.05 to 1 g / m ² , more preferably 0.05 to 0.5 g / m ^2. Apply as follows. Although there is no restriction | limiting in the coating method, A gravure coat method, a reverse coat method, a direct coat method etc. are used, and the gravure coat method is preferable. After the coating, the leather-like sheet of the present invention in which the surface layer composed of unmodified or modified hollow nanosilica particles and a polymer elastic body is formed on the surface of the fibrous base material and / or the coating layer surface by removing the solvent according to a conventional method Is obtained. By forming the surface layer, the leather-like sheet of the present invention exhibits an excellent wet grip property even if the surface is not porous. Even when the dispersion is applied to the surface of a base material such as wood, stone, metal, plastic, paper, natural leather instead of the surface of the fiber base material or coating layer, the wet grip by the surface-modified particles is used. A sex improvement effect is obtained.

In the present invention, it is preferable that 10% or more of the surface of the fibrous base material is covered with a silver surface portion. When the surface of the fibrous base material is covered with 100% silver part, it becomes a so-called silver-finished leather-like sheet, and preferred uses of the silver-finished leather-like sheet are volleyball (indoor), beach volleyball, handball, soccer Surface materials for game balls used in rugby, American football, golf and baseball, materials for sports gloves such as marine sports, materials for insoles and insoles, materials for sandals, and vehicle seats It is suitably used as a surface material and other materials that require gripping properties when wet, such as floor materials, various grips, and shoe soles. The case where it is used as a surface material for a game ball such as volleyball will be described below.

The basic structure of a game ball such as a volleyball is composed of, for example, a tube (bladder, usually made of rubber), a cover layer (usually made of rubber), a pincushion reinforcing layer, and a skin layer that can be inflated by air from the inside. In the game ball of the present invention, as long as the skin layer is formed of the leather-like sheet, other structures are not particularly limited, and a conventionally used game ball structure can be adopted. The surface material for game balls such as volleyball is basically the same as the leather-like sheet described above, but the resin layer 1 (surface layer, surface layer and coating layer, or coating layer) formed on the fibrous base material 2. It is preferable to form a large number of continuous protrusions 4 and discontinuous recesses 3 on the surface of the layer (see FIG. 1). Here, the “discontinuous recesses” are, for example, a large number of independent concave shapes (recesses) formed by pressing a large number of independent convex shapes arranged at intervals on a flat sheet surface. Say. As a method for forming the “discontinuous recesses”, any conventionally known method can be adopted as long as a desired recess shape can be stably provided. For example, a method in which the surface of the resin layer 1 is embossed with an embossing roll having a desired convex shape, or a polymer formed by casting and solidifying a polymer elastic body fluid on a release paper having a desired convex shape. A method of laminating the elastic sheet on the surface of the fibrous base material can be employed.

Each concave portion preferably has a vertical projection area of 1 to 5 mm ² , an average interval between adjacent concave portions of 0.5 to 3 mm, and a depth of the concave portion of 50 to 500 μm. In the method of using the release paper described above, the production of the release paper is limited to the surface layer, the surface layer and the coating layer, or the depth of the concave portion of the coating layer, and the release paper having discontinuous convex portions. When the polymer elastic body solution is applied, the deeper the convex part (surface layer, surface layer and coating layer, or concave part of the coating layer) on the release paper, the more likely the bubbles are to be formed around the convex part. This is a suitable method when the depth is less than 150 μm. On the other hand, the method of embossing with an embossing roll or the like may use an embossing roll having a convex portion corresponding to the intended depth of the concave portion, and the depth is not so limited. Therefore, in consideration of industrial productivity, a method of forming irregularities with an embossing roll or the like is preferable to a method of using a release paper. When forming a desired recessed part using an embossing roll, it can carry out by setting suitably the convex part height of the roll to be used, and the temperature, pressure, and time conditions of the roll. Although these conditions are not particularly limited, the height of the convex part of the roll is 80 to 700 μm, the roll temperature is 150 to 180 ° C., the press pressure (linear pressure) is 5 to 50 kg / cm, and the processing speed is 0.5 to 5 m / min. To obtain a desired recess depth. When unevenness is formed by an embossing roll, the fiber entangled body may be impregnated with a polymer elastic body and then further impregnated with the same type and / or different types of polymer elastic bodies to be solidified into a porous form. If it does in this way, embossing can be performed successfully.

As a surface shape of a game ball used for ball games such as volleyball, it is necessary that at least one concave portion touches the fingertip when the player randomly holds the ball. Accordingly, the depth of the recess is preferably 50 to 500 μm, more preferably 150 to 300 μm. When the depth of the recess is less than 50 μm, it becomes easy to slip when it gets wet with sweat or water, so it is not effective especially in toss control and suppresses orbital shake during flight such as serve It is difficult to obtain an effect. The design effect is also small, and the merchantability is reduced. On the other hand, when the depth of the recess exceeds 300 μm, the grip property when wet with sweat or water is further improved, and the control property when raising the toss is further improved. When the depth of the recess exceeds 500 μm, the ball is too caught on the fingertip, and the controllability of the ball is lowered. In addition, as shown in FIG. 3, the “depth of the concave portion” in the present invention means that the distance (D) from the surface of the convex portion to the deepest portion of the concave portion in the coating layer is a cross-sectional photograph in the thickness direction. The average value of 10 measured values.

The vertical projection area of the concave portion on the surface of the resin layer 1 is preferably 1 to 5 mm ² , more preferably 2 to 3 mm ² . When the vertical projection area exceeds 5 mm ² , the ball is too caught on the fingertip when raising the toss, and the controllability of the ball deteriorates. In addition, the wear resistance of the ball is reduced. When the vertical projection area is less than 1 mm ² , there is almost no catching on the finger, and even slipping when wet with sweat or water makes the controllability when tossing worsens. In addition, the design effect is small, and the merchantability is low. In the cross section passing through the deepest part of the concave portion on the surface of the resin layer 1, when the concave surface and the surface of the convex portion adjacent thereto are connected by a continuous curve, the angle formed by the perpendicular of the flat portion and the tangent of the concave surface is 45 ° This portion is defined as a boundary (B) between the concave portion and the flat portion (see FIG. 4). On the other hand, if the surface shape is broken, that point is defined as the boundary (B) between the concave portion and the flat portion (see FIG. 5). The projected area in the direction perpendicular to the surface of the resin layer 1 in the recessed area surrounded by the boundary line (shown by X in the cross sections of FIGS. 4 and 5) is referred to as “vertical projected area of the recessed section”.

The sum of the vertical projection areas of the individual recesses is preferably 3 to 30%, more preferably 8 to 25% with respect to the total surface area of the resin layer 1. If the ratio of the sum of the vertical projection areas of the individual recesses is less than 3%, the controllability when tossing is poor, and the trajectory during flight such as serve will be blurred. In addition, the design effect is small, and the merchantability is low. On the other hand, if it exceeds 30%, when the toss is raised, the ball is caught too hard on the fingertip, and the controllability of the ball is deteriorated. Further, the cross-sectional shape in the thickness direction of the concave portion of the resin layer 1 is preferably an arc shape, a semicircular shape or a trapezoidal shape, and the three-dimensional shape is preferably a hemispherical shape, a truncated cone shape or a truncated pyramid shape. Here, “hemisphere” does not mean a complete hemisphere, but means that the shape is substantially hemispherical. Further, “trapezoidal shape” does not mean a complete trapezoid, but means that the shape is substantially trapezoidal. For example, the base may not be a straight line but may be slightly convex. Similarly, an arcuate shape, a semicircular shape, a truncated cone shape, or a truncated pyramid shape may be used as long as they are roughly in such a shape. By making the concave shape hemispherical or trapezoidal, not only can you get a very delicate catch on the fingertip when tossing, but the total controllability including serve and other play is well balanced It will be obtained.

The average distance between the recesses on the surface of the resin layer 1 is preferably 0.5 to 3 mm. When the thickness is less than 0.5 mm, the concave portions are too close to each other and the shape of the convex portions is partially sharpened, so that the softness, cushioning property and touch feeling, and surface wear resistance are inferior. Moreover, when exceeding 3 mm, fitting property and grip property are inferior. The average distance between the recesses is more preferably 1 to 2 mm. The “average interval between recesses” is an average obtained by photographing the surface with an electron microscope, selecting 10 arbitrary recesses, and measuring the shortest distance between a specific point on the outer periphery of the recess and the outer periphery of the adjacent recess. Value. The closed curve defined by the boundary B is defined as the outer periphery of the recess.

Even if the convex portion (primary convex portion) on the surface of the resin layer 1 is formed with the secondary concave portion 5 and the secondary convex portion 6 having a depth less than the depth of the concave portion (primary concave portion) and 10 to 100 μm. Good (Figure 2). The shape of the secondary concavo-convex portion is not particularly limited, but is arranged on a straight line or curve in two or more directions such as a lattice shape, a concentric circle shape, a radial shape, etc. (see FIG. 6) in order to obtain a non-slip property uniformly in all directions. It may be a non-uniform shape consisting of a plurality of straight lines or curves, a discontinuous concave shape similar to the primary concave portion, or a combination thereof. From the viewpoint of excellent grip and design when wet with sweat, it is preferable that the discontinuous recess shape similar to the primary recess is the shape of the secondary recess.

The depth of the secondary recess is preferably in the range of 10 to 100 μm and less than the depth of the primary recess, and more preferably 20 to 70 μm. By making the depth of the secondary recess 10 μm or more, the fingertip and the ball are sufficiently caught, and the toss control is excellent. By setting the depth of the secondary recess to 100 μm or less, the wear resistance and the surface feel are excellent. Furthermore, by making the depth less than the depth of the concave portion, it is possible to have excellent wear resistance and surface tactile feel and to suppress adhesion of dirt.

The secondary recesses are discontinuous, the vertical projection area is preferably 0.01 to 1 mm ² , and the ratio of the sum of the vertical projection areas of the individual secondary recesses to the surface area of the resin layer is preferably 1 to 30%. . When the vertical projection area of the secondary recess is 0.01 to 1 mm ^2, it is preferable in that the surface feel is smooth. The secondary recess is discontinuous, and the ratio of the sum of the vertical projection areas is 1 to 30. When it is%, the ball and the fingertip are sufficiently easily engaged with each other, so that the grip performance is further improved. Further, it is preferable in that the straightness of the ball is superior, and the trajectory is less likely to be shaken particularly in a serve where the flight distance of the ball is long, and more preferably 3 to 20%. The secondary uneven portion is preferably formed on the upper surface rather than the side surface of the convex portion (see FIG. 2).

As a method for forming the secondary unevenness, there are a method of simultaneously forming the recessed portion and the secondary unevenness using a release paper capable of forming the recessed portion and the secondary unevenness, a method of embossing the secondary unevenness by an embossing process, etc. However, in consideration of industrial productivity, a method of forming by embossing is a preferable method rather than a method of using release paper. When using the embossing roll to form the desired secondary irregularities, the height of the convex portion of the embossing roll to be used and the conditions of the temperature, pressure and time of the embossing roll can be appropriately set. These conditions are not particularly limited, but the embossing roll has a convex height of 80 to 700 μm, a roll temperature of 150 to 180 ° C., a pressing pressure of 5 to 50 kg / cm, and a time of 10 to 120 seconds. Next unevenness can be formed. It is economical to prepare and use an embossing roll in a shape that can form discontinuous recesses and secondary irregularities in advance so that discontinuous recesses and secondary irregularities can be formed simultaneously by a single embossing process. This is the preferred method.

A game ball having a surface layer composed of a leather-like sheet having a large number of discontinuous recesses as described above, particularly volleyball, has good contact control between the fingertip and the ball surface when tossed, and thus the controllability of the ball is very good. Further, by providing the secondary unevenness, the grip property when wet (when wet with sweat or water) can be further improved by a synergistic effect with the surface layer containing the hollow nanosilica particles. In addition, since trajectory fluctuations during flight such as serve are suppressed and the degree of stall during flight is smooth, the controllability of the ball is good throughout the game. It is also excellent in design. The leather-like sheet of the present invention in which irregularities are formed on the surface layer after forming the surface layer or the coating layer and the surface layer on the surface of the fibrous base material, and hollow nanosilica as described above after the irregularities are formed on the surface of the coating layer The leather-like sheet of the present invention in which a particle dispersion is applied to form a surface layer is particularly suitable as a surface material of a ball that is directly hit by a hand such as volleyball or beach volleyball.
(2) Suede or semi-silver leather-like sheet

The suede-like leather-like sheet of the present invention comprises a fiber entangled body composed of a bundle of ultrafine fibers having an average fineness of 0.3 dtex or less, a polymer elastic body (fibrous substrate) present inside the fiber entangled body, and a surface thereof. It consists of the formed napped ultrafine fibers, and hollow nanosilica particles exist on the napped surfaces (the surface of the fibrous base material on which napped fibers are formed and the napped ultrafine fiber surface). Further, the semi-silver leather-like sheet of the present invention has a napped portion made of fibers constituting the covering portion and the fibrous base material on at least one surface of the fibrous base material. Hollow nanosilica particles are present on the surface of the fibrous base material and the surface of the napped ultrafine fibers).

In the case of producing a suede-like or semi-silver-like leather-like sheet, at least one surface of the fibrous base material is subjected to raising treatment to obtain a raised sheet having ultrafine fiber napping. Buffing treatment and hair styling conditions, such as the sandpaper count used for the buffing treatment, grinding speed, and the nap length when raising the hair by appropriately selecting the pressure for pressing the sandpaper to the fiber substrate surface Can be adjusted. The ultrafine fiber napping may be present on the entire surface of one side of the sheet, or may be present on the entire surface of both sides. May be present in the form of a spot.

The napped sheet obtained in this way may have the following structure in order to make creases and textures closer to natural leather. That is, in the step of producing a sheet, a sheet having a structure in which the fineness differs between the back and the front of the sheet obtained by impregnating the elastic polymer after laminating two or more layers of non-woven fabrics having different fineness, Except for the difference, the sheet-like material obtained by the same method may have a multilayer structure bonded with an adhesive. Furthermore, for the purpose of providing a waterproof function, for example, at least one layer excluding the surface layer of a sheet composed of a laminate of two or more layers may have a structure in which a waterproof film-like material is used. In addition, the raised sheet is colored with a colorant such as a dye or a pigment to give a desired appearance, or a softener, a slimming agent, a water repellent, a hydrophilic agent to impart a desired texture or functionality. You may give well-known processing agents, such as an agent, a light resistance agent, antioxidant, antifouling agent, a flame retardant, an antibacterial agent, an antifungal agent, and an aromatic agent, individually or in combination. The step of imparting may be after imparting hollow nanosilica particles to be described later, as long as the grip property intended by the present invention is not impaired.

Furthermore, the concave / convex pattern may be imparted by embossing or the like before and after imparting the hollow nanosilica particles. By embossing, it can have a two-colored appearance, a patterned pattern, a drawn pattern, a blood-skinned pattern, etc. Variations are obtained.

Next, hollow nano silica particles are applied to the surface of the napped sheet. The hollow nanosilica particles may have a modified surface. Details of the unmodified and modified hollow nanosilica particles are as described above.

As a method of attaching unmodified or modified hollow nanosilica particles to the raised surface or raised portion of the raised sheet, it selectively adheres to the surface of the fibrous base material such as gravure coating method, spray coating method, knife coating method, bar coating method, etc. And a method of impregnating and drying to adhere to all layers in the thickness direction of the fibrous base material. Hollow nanosilica particles include aliphatic alcohols such as methanol and ethanol, aliphatic hydrocarbons such as n-hexane, aromatic hydrocarbons such as toluene and xylene, acetone, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK). It is used as a dispersion liquid dispersed in an organic solvent such as ketones or a dispersion medium such as water. The attachment method is not particularly limited, but in the production of sports gloves and work gloves where surface grip is important, the method of applying with a gravure roll is preferably used in terms of the application amount during application processing and the stability of operation. It is done. In the case of using a gravure roll, 30 to 300 mesh can usually be used, and 50 to 200 mesh is preferably used in terms of excellent transferability to the napped surface of the napped sheet. In order to obtain the desired grip property, the required coating amount may be applied using a coarse mesh that can be transferred at one time, but a finer mesh is used in order to obtain a more elegant surface raised feeling. In some cases, the application amount may be divided into a plurality of times, and the application method to be employed may be selected as appropriate.

The solid content concentration of the unmodified or modified hollow nanosilica particles in the dispersion is preferably 1 to 10% by mass. If the concentration is too low, it will excessively penetrate into the suede-like leather-like sheet at the time of application, while if the concentration is too high, the amount of hollow nanosilica particles will increase and the napped appearance, texture, etc. will be reduced or applied. Since unmodified or modified hollow nanosilica particles that are sometimes present in the form of primary particles may be abruptly reduced, it is difficult to obtain the desired presence state on the surface if the preferred concentration range is exceeded. In addition, it can be applied to the napped surface after drying (after removal of the solvent) so that the applied amount is 0.02 to 0.8 g / m ² with a soft texture without impairing the elegant nap and color tone. However, it is preferable because it has a good grip property when dry and wet. A more preferable coating amount is 0.05 to 0.5 g / m ² . After application, the suede-like leather-like sheet of the present invention in which unmodified or modified hollow nanosilica particles are present on the napped surface is obtained by removing the solvent according to a conventional method. Since the coating amount is a coating amount per side, when unmodified or modified hollow nanosilica particles are present on both surfaces of the suede leather-like sheet, the coating amount on each side is 0.02 to 0.8 g. It is preferable to apply so as to be / m ² . Moreover, the application amount on each surface may be the same or different.

As the order of attaching the non-modified or modified hollow nanosilica particles to the fibrous base material, there are a method of applying after raising the surface by the above-described method and a method of raising the surface after applying to the fibrous base material. In general, it is more efficient to apply after brushing because all the unmodified or modified hollow nanosilica particles applied remain on the surface of the leather-like sheet. There is no particular limitation as long as unmodified or modified hollow nanosilica particles are attached. Furthermore, in the present invention, if necessary, it includes a step of applying a polymer elastic body covering the surface to form a covering portion, or embossing the surface, but these steps are also included. The unmodified or modified hollow nanosilica particles may be attached at any stage.

The suede-like leather-like sheet obtained as described above is particularly suitable for sports gloves, work gloves, sports shoes and sandals as a material having a grip and high-quality appearance and touch. However, it is useful as a material such as furniture to which the unique tactile sensation of the present invention can be applied, and other gloves, shoes and insoles thereof.

The semi-silver-tone leather-like sheet of the present invention has a covering portion of the fibrous base material, that is, a portion made of a polymer elastic body on the surface of the fibrous base material and substantially covering the fibrous base material. Here, “substantially” means that napped fibers and napped fiber bundles having a lighting effect do not protrude on the covering portion made of the polymer elastic body on the fibrous base material. Therefore, lying fibers or fiber bundles (napped fibers and napped fiber bundles that do not show a lighting effect) may be present on the surface of the coated portion. As a method for obtaining such a structure, the following various methods can be employed. For example, there is a method of performing gravure printing or spray coating a dispersion, solution or melt of a polymer elastic body on the surface of a fibrous base material. In the case of gravure printing, a gravure roll of 50 to 200 mesh is usually used in many cases, but the present invention is not limited to this, and coating using rolls having various patterns may be performed.

The polymer elastic body forming the covering portion is preferably a resin having a certain degree of grip rather than a slippery resin. For example, synthetic rubber, polyolefin-based thermoplastic elastomer, polyester elastomer, polyvinyl chloride resin, A polyurethane-based resin or the like can be used. Among these, from the viewpoint of balance such as elasticity, softness, and abrasion resistance, a polyurethane-based resin is preferably used in the same manner as the polymer elastic body contained in the fiber entangled body.

The polyurethane-based resin for coating may be the same as or different from the polyurethane contained in the fiber entangled body. However, in order to obtain adhesion between the covering polyurethane and the polyurethane contained in the fibrous base material, it is preferably selected from the same series of polyurethane resins. If necessary, a mixture of a plurality of types of polyurethane-based resins may be used, and a polymer composition mainly composed of polyurethane may be used by adding a polymer such as synthetic rubber, polyester elastomer, or polyvinyl chloride. You can also. From the standpoint of hydrolysis resistance and elasticity, a polyurethane resin in which the polymer diol component is a polyether polymer diol such as polytetramethylene glycol is preferred.

The polymer elastic body forming the covering portion is colored with a colorant such as a dye or a pigment in order to give a desired appearance, or a slimming agent, a water repellent, You may contain well-known processing agents, such as a hydrophilic agent, light resistance agent, antioxidant, antifouling agent, a flame retardant, an antibacterial agent, an antifungal agent, and an aromatic agent, individually or in combination. Furthermore, you may contain the said hollow nano silica particle and / or surface modification particle | grains.

The coated portion has the following aspects (1) to (4). In the present invention, the desired grip properties can be obtained if the unmodified or modified hollow nanosilica particles are attached to the raised portion. . In particular, (2), (3) and (4) are preferable because a synergistic effect is obtained.
(1) The coating portion contains a polymer elastic body and substantially does not contain unmodified and modified hollow nanosilica particles.
(2) The coating portion includes a polymer elastic body and unmodified hollow nanosilica particles.
(3) The coating portion includes a polymer elastic body and modified hollow nanosilica particles.
(4) The modified hollow nanosilica particles are attached to at least a part of the surface of the covering portion made of a polymer elastic body. Each case will be described in detail.

In the case of the covering portion (1), the target gripping property is due to the frictional resistance of the fibrous base material portion having napping, so that the area ratio (A / B) of the covering portion (A) and napping portion (B) is 10 / It is preferably 90 to 60/40, more preferably 20/80 to 50/50. If it exceeds 60/40, the grip performance tends to decrease, such being undesirable. On the other hand, if it is less than 10/90, a suede appearance is obtained, and the desired semi-silver appearance is not obtained.

In the case of the covering portions (2) and (3), the desired grip properties can be obtained from both the napped portion and the covering portion, and therefore the area ratio (A / B) is preferably 10/90 to 90/10, More preferably, it is 20/80 to 80/20. If it is out of the above range, a semi-silver-like appearance is not obtained, and if it is less than 10/90, a suede-like appearance is obtained.

The coated portion (1), (2) or (3) is a high-strength material in which unmodified or modified hollow nanosilica particles are dispersed as necessary in a fibrous base material having napped fibers to which unmodified or modified hollow nanosilica particles are attached. It can be obtained by applying a molecular elastic body solution. Moreover, it can also be embossed by embossing etc. as needed. In this case, the step of applying the polymer elastic body and the step of embossing may be performed in this order or in the reverse order.

The concentration of the solid content of the polymer elastomer solution in which the unmodified or modified hollow nanosilica particles for forming the coating part (2) or (3) are dispersed (the total of the unmodified or modified hollow nanosilica particles and the polymer elastomer) is The content is preferably 5 to 20% by mass. The content of unmodified or modified hollow nanosilica particles is preferably 5 to 15 parts by mass with respect to 100 parts by mass of the elastic polymer.

The surface-modified hollow nanosilica particles are attached to at least a part of the surface of the coating part (4). If the hollow nanosilica particles are not modified, the adhesion between the polymer elastic body and the hollow nanosilica particles is low, and the hollow nanosilica particles fall off while using the product obtained from the leather-like sheet, and the synergistic effect on the grip performance is reduced. Tend. Since the desired grip property can be obtained from both the napped portion and the covering portion as in the covering portions (2) and (3), the area ratio (A / B) is preferably 10/90 to 90/10, and more It is preferably 20/80 to 80/20. Outside this range, a semi-silver-like appearance is not obtained, and when it is less than 10/90, a suede appearance is obtained.

The coated portion (4) is formed by applying a polymer elastic body to a napped sheet having surface-modified hollow nanosilica particles, and then applying the surface-modified hollow nanosilica particles, as in the coated portions (1) to (3). Can be obtained. Moreover, it can also emboss by embossing etc. as needed, In this case, the process of apply | coating a polymeric elastic body and the process of embossing may be performed in this order, and may be performed in the reverse order.

The covering part (4) further performs (a) a step of forming nap on the fibrous base material, (b) a step of applying a polymer elastic body, and (c) a step of embossing as necessary, It can be obtained by applying surface-modified hollow nanosilica particles to the surface of the obtained leather-like sheet. The above steps (a), (b), and (c) are performed as follows: (a) → (b) → (c), (a) → (c) → (b), (b) → (a) → (c ), (B) → (c) → (a), (c) → (a) → (b), and (c) → (b) → (a). Depending on the order, the appearance in which the pressing mold is emphasized, or the two-colored feeling is generated only by applying the polymer elastic body to the convex portion of the pressing mold, or the convex portion is raised and the concave portion is not raised. Appearance and various variations can be obtained, so you can use them as you like.

Examples of the solvent for the polymer elastic body solution used for forming the coating portion include ketones such as cyclohexanone and acetone, amides such as dimethylformamide, toluene, and the like. These solvents may be used alone or in combination of two or more.

The semi-silver-tone leather-like sheet obtained as described above has a gripping property, a material with a high-quality appearance and touch that has a lighting effect, materials such as sports gloves, work gloves, sports shoes and sandals. It is suitably used as a material for footbeds and the like.

EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited to these Examples. In the examples, parts and% are based on mass unless otherwise specified. Each evaluation was performed by the following methods.
(1) Volleyball Wet Grip When 10 players practice long-term volleyball (indoor) for a long time, and grip with a sweaty hand or finger, the gripping ability when handling the ball with the following criteria A to A C was evaluated. The most common criteria among the 10 people's evaluation was adopted as the wet grip evaluation.
A: The ball does not slip and has a sufficient grip.
B: The ball does not slide frequently but the grip is not sufficient.
C: The ball slips frequently and lacks grip.
(2) Gripping property of sandals when wet Sandals were made using the obtained leather-like sheet as a top of the sandals, and 10 people put on the sandals with bare feet and had a walking test. The walking test was performed in a dry state of the sandals and a wet state in which the sandals were consciously soaked in water for 1 minute and the leather-like sheet was sufficiently soaked with water. Evaluation was performed according to the following criteria A to C. The standard that was most common among the 10 evaluations was adopted as the evaluation of grip performance.
A: The feet did not slip, the grip was sufficient, and it was easy to walk.
B: The frequency with which the foot slips is low, but the grip is not sufficient.
C: The feet slipped frequently and it was difficult to walk.
(3) Coverage ratio (area ratio of covered part)
After photographing the surface of the leather-like sheet with an electron microscope at a magnification of 100, a polymer elastic body visible from the surface was colored, and the area ratio of the colored portion was determined.

Example 1
50 parts of polyethylene (sea component) and 50 parts of 6-nylon (island component) were melt-spun in the same melt system to produce sea-island fibers with a fineness of 15 dtex. This sea-island fiber was stretched 2.5 times and crimped, and then cut into a fiber length of 51 mm. The obtained staple was opened with a card and made into a fiber web with a cross wrapper webber. The fiber webs were overlapped, and a fiber entanglement with a basis weight of 650 g / m ² was obtained by needle punching.
13% dimethylformamide (DMF) of polyester-based polyurethane (100% modulus: 100 kg / cm ² ) obtained by copolymerization of polyethylene propylene adipate, 4,4 ″ -diphenylmethane diisocyanate (MDI) and ethylene glycol (EG) ) The resulting fiber entangled body was impregnated. Immediately thereafter, the same 26% DMF solution of a polyester-based polyurethane was 40 g / m ² coating permeates the fiber-entangled body surface. Further, on the upper surface, a polycarbonate-based polyurethane (100% modulus: 40 kg / cm ^{2) in} which the main components are polyhexacarbonate glycol, polymethylenepropylene adipate and methylenediamine, and n-hexane diisocyanate, MDI and EG are further copolymerized. ) Of 20% DMF was applied at 75 g / m ² . The fiber entangled body impregnated with polyurethane was immersed in a coagulation bath (40 ° C.) of DMF / water = 30/70 for 30 minutes to coagulate the polyurethane in a porous state. Subsequently, after washing with water, polyethylene in the sea-island fiber is extracted and removed with toluene to convert it into ultrafine fibers having an average fineness of 0.01 dtex, and a thickness of 1.6 mm consisting of a fiber bundle of 6-nylon ultrafine fibers and porous polyurethane. A fibrous base material was obtained.
A 10% solution of a polyester-based polyurethane containing a blue pigment was applied to the surface of the fibrous substrate with a gravure roll to form a coating layer having a total thickness of about 200 μm of the porous layer and the non-porous layer. Thereafter, using an embossing roll having a trapezoidal convex part with a height of 0.5 mm and a vertical projection area of 4 mm ² , the embossing roll was performed at a roll temperature of 170 ° C., a pressing pressure of 8 kg / cm, and a processing speed of 1 m / min. It was. The depth of the discontinuous recesses formed on the surface of the coating layer was almost the same in any recess, and the average value was 200 μm. Further, the vertical projection area of the recess was substantially the same, and the average value was 2 mm ² . The average interval between the recesses was 2.5 mm, and the total vertical projection area of the recesses was 9% of the coating layer surface area.
Uniform containing 10% hollow nanosilica particles having a primary particle size of 50 to 150 nm, a silica shell thickness of 5 to 15 nm, and shell wall pores of 2 nm or less (BET method) based on the solid content of the polycarbonate-based polyurethane (binder) A dispersion (dispersion medium: cyclohexanone / acetone / DMF mixed solvent (50/40/10)) was prepared. This dispersion was diluted twice with the same dispersion medium. The diluted dispersion was applied onto the uneven surface of the coating layer using a 150 mesh gravure roll (application amount: 1.5 g / m ² as the total amount of hollow nanosilica particles and binder), and a nonporous surface layer was applied. Formed.
Using the obtained leather-like sheet as a surface material, a volleyball was produced according to a conventional method. The evaluation of the grip property when wet of the obtained volleyball was A.

Example 2
In the same manner as in Example 1, a 1.6 mm-thick fibrous base material comprising a fiber bundle of 6-nylon ultrafine fibers and porous polyurethane was obtained.
A 10% solution of polyester polyurethane containing a blue pigment was applied to the surface of the fibrous base material with a gravure roll to form a coating layer having a thickness of about 5 μm. Thereafter, using an embossing roll having a trapezoidal convex part with a height of 0.5 mm and a vertical projection area of 4 mm ² , the embossing roll was performed at a roll temperature of 170 ° C., a pressing pressure of 8 kg / cm, and a processing speed of 1 m / min. It was. The depth of the discontinuous recesses formed on the surface of the coating layer was almost the same in any recess, and the average value was 200 μm. Further, the vertical projection area of the recess was substantially the same, and the average value was 2 mm ² . The average interval between the recesses was 2.5 mm, and the total vertical projection area of the recesses was 9% of the coating layer surface area.
Surface-modified particles (“Nanotouch” (registered trademark)) in which hollow nanosilica particles having a primary particle size of 50 to 150 nm, a silica shell thickness of 5 to 15 nm, and shell wall pores of 2 nm or less (BET method) are modified with isocyanate groups A uniform dispersion liquid (dispersion medium: cyclohexanone / acetone / DMF mixed solvent (50/40/10)) containing 10% of Grandex Co., Ltd. with respect to the solid content of the polycarbonate-based polyurethane (binder) was prepared. This dispersion was diluted twice with the same dispersion medium. The diluted dispersion was applied onto the uneven surface of the coating layer using a 150 mesh gravure roll (coating amount: 1.5 g / m ² as the total amount of hollow nanosilica particles and binder) to form a surface layer.
Using the obtained leather-like sheet as a surface material, a volleyball was produced according to a conventional method. The evaluation of the grip property when wet of the obtained volleyball was A.

Example 3
Surface-modified particles (“Nanotouch” (registered trademark)) in which hollow nanosilica particles having a primary particle size of 50 to 150 nm, a silica shell thickness of 5 to 15 nm, and shell wall pores of 2 nm or less (BET method) are modified with isocyanate groups A leather-like sheet was obtained in the same manner as in Example 2 except that a uniform dispersion (dispersion medium: methyl ethyl ketone) containing 10% of Grandex Co., Ltd. was diluted 10 times with methyl ethyl ketone.
Using the obtained leather-like sheet as a surface material, a volleyball was produced according to a conventional method. The evaluation of the grip property when wet of the obtained volleyball was A.

Example 4
Nylon-6 chips and low-density polyethylene chips are mixed at a mass ratio of 50:50, melt-spun by an extruder, and sea-island mixed spinning fibers containing polyethylene as a sea component are spun and drawn, crimped, and cut. 4 dtex, 51 mm long short fibers were produced. The web obtained by opening the short fibers with a card was stacked with a cross wrapper, and further needle punching at 700 punch / cm ² was performed using a needle punching machine to obtain an entangled nonwoven fabric. The entangled nonwoven fabric obtained was impregnated with a dimethylformamide (DMF) solution of a poly-3-methylpentane adipate / polyethylene glycol copolymer polyurethane resin and then introduced into a water / DMF mixed bath to wet-coagulate the polyurethane resin. . Next, it was introduced into a toluene bath heated to 85 to 95 ° C. and the immersion-drawing solution was repeated several times to extract and remove the sea component polyethylene of the sea-island fiber. When polyethylene was not extracted, the solution was finally squeezed, and the entangled nonwoven fabric was immediately introduced into hot water at about 100 to 120 ° C. to completely remove the remaining toluene azeotropically. After impregnating the softening agent, the fiber is dried in a steam dryer at about 130 to 150 ° C., so that the fiber has a basis weight of 170 g / m ² , a thickness of 0.45 mm, and a ratio of nylon ultrafine fiber to polyurethane resin of 75/25. A quality substrate was obtained. The average fineness of the nylon ultrafine fibers of the obtained fibrous base material was 0.007 dtex. One side of this fibrous base material is buffed with sandpaper, and further dyed in dark gray with a metal complex hydrochloric acid dye using a Wins dyeing machine, so that a dark gray color having a napped surface composed of the nylon ultrafine fibers is obtained. A suede leather-like sheet was obtained.

A uniform MEK dispersion containing 2% of hollow nanosilica particles having a primary particle size of 50 to 150 nm, a silica shell thickness of 5 to 15 nm, and shell wall pores of 2 nm or less (BET method), surface-modified with isocyanate groups It was adjusted. This dispersion was applied to the surface of the suede-like leather-like sheet using a 150 mesh gravure roll (coating amount (solid content): hollow nanosilica particles 0.2 g / m ² ), and steam dried at about 110 to 130 ° C. By drying in-machine, a suede-like leather-like sheet with hollow nanosilica particles attached so as to cover a part of the napped surface made of ultrafine fibers was produced.
The obtained suede-like leather-like sheet had softness and an elegant napped appearance like natural leather suede, and was excellent in dry and wet grip when touched by hand. The dry time is an evaluation after the suede-like leather-like sheet is left in a standard state (temperature: 20 ° C., humidity: 45%) for 24 hours or more. The wet-time is a suede-like leather-like sheet. It is an evaluation in a state in which excess water is wiped off with a filter paper after being immersed in distilled water for 10 minutes and taken out.
Further, this suede-like leather-like sheet was cut into a size of 3 cm × 12 cm to obtain a measurement sample, and the surface of the hollow nanosilica particles adhered was loaded with a friction tester KES-SE (manufactured by Kato Tech Co., Ltd.) with a load of 25 g, The dynamic friction coefficient was measured three times under the condition of 1 mm / sec, and the average of the three measurements was taken as the dynamic friction coefficient of the sample. The evaluation results are shown in Table 1.

Example 5
Ethylene-modified polyvinyl alcohol as sea component polymer (ethylene unit content 8.5 mol%, polymerization degree 380, saponification degree 98.7 mol%), and island component polymer isophthalic acid-modified polyethylene terephthalate (content of isophthalic acid unit) 6.0 mol%) was melted individually, and the molten polymer was applied to a composite spinning die in which a large number of nozzle holes capable of spinning 25 islands of islands were arranged in parallel. It was supplied while adjusting the pressure balance so that the ratio of sea component / island component = 25/75, and was discharged from the nozzle hole at a base temperature of 250 ° C. Under the condition that the average spinning speed is 3600 m / min, it is pulled and thinned with an air jet / nozzle type suction device, and a sea island type fiber with an average fineness of 2.4 dtex is spun. Continuously collected. The amount of deposition was adjusted by the moving speed of the net, and further pressed with an embossing roll at 80 ° C. to obtain a long fiber web having a basis weight of 30 g / m ² .

After spraying a mixed oil agent composed of a mineral oil-based slipping oil and an antistatic agent on the surface of the long fiber web, it is continuously folded by a cross wrapper device to form a 14-layer laminar long fiber web, and the barb is thick. A three-dimensional entanglement treatment was performed by a needle punch method with a total number of punches of 1700 punches / cm ² from both sides, including conditions penetrating in the vertical direction, to obtain a fiber entangled body made of sea-island type fibers.
Next, water was evenly applied to both sides of the fiber entangled body, and immediately after that, in the atmosphere at a temperature of 75 ° C. and a relative humidity of 95%, almost no tension or friction stress acted in the length direction and the width direction, and the residence time 4 The wet heat shrinkage treatment was performed by continuously passing under the condition of minutes. Thereafter, the fiber entangled body is pressed between metal rolls at 120 ° C. and dried while compressing and smoothing the surface, and then the entire fiber entangled body is dried in an atmosphere at 120 ° C. to obtain a dense 1125 g / m ² basis weight. A fiber entangled body was obtained.

The resulting fiber entangled body is impregnated with an aqueous dispersion (solid content concentration 11 mass%) of a polyurethane composition mainly composed of polycarbonate / ether-based polyurethane, so that the liquid content is 50 with respect to the fiber entangled mass 100. It was pressed with a roll and heat-coagulated by applying an infrared heater for 1 minute under conditions where the fiber entangled surface temperature was 80 ° C., then dried in an atmosphere of 120 ° C., and then immediately in an atmosphere of 150 ° C. for 2 minutes. The polyurethane composition was made to exist in the space | gap between sea-island type fibers by performing a curing process. Next, after treatment with hot water at 90 ° C. for 20 minutes in a liquid dyeing machine to extract and remove the modified polyvinyl alcohol in the sea-island fiber, drying is performed at 120 ° C., so that the ultrafine fiber bundle of the modified polyethylene terephthalate is removed. A fibrous base material having a thickness of 1.4 mm in which the polyurethane composition was contained inside the resulting fiber entangled body was obtained.

The fibrous base material was divided into two in the thickness direction, and then the non-divided surface was buffed with sandpaper to raise and trim the hair, thereby forming napped fibers made of ultrafine fibers of modified polyethylene terephthalate. Furthermore, after dyeing with a disperse dye using a liquid dyeing machine, brushing was performed and the hair was finished to obtain a dark gray suede-like leather-like sheet having a thickness of 0.6 mm.

A uniform aqueous dispersion containing 2% hollow nanosilica particles having a primary particle size of 50 to 150 nm, a silica shell thickness of 5 to 15 nm, and shell wall pores of 2 nm or less (BET method) was prepared. This dispersion is applied on the surface of the suede leather-like sheet using a 150 mesh gravure roll (coating amount: hollow nanosilica particles 0.2 g / m ² ) and dried in a steam dryer at about 110 to 130 ° C. Thus, a suede-like leather-like sheet having hollow nanosilica particles attached to the fiber surface was produced.
The resulting suede-like leather-like sheet has a soft, low-resilience feel and an elegant napped appearance, similar to natural leather suede, and feels dry and wet when touched by hand. It was excellent in nature.

Comparative Example 1
A dark gray nap sheet prepared in the same manner as in Example 4 was evaluated as a suede leather-like sheet in the same manner as in Example 4 without applying anything to the surface. Soft and graceful napped appearance like natural leather suede is as good as in Example 4, but the grip when dry and wet when touched by hand is sufficient for the intended application. I couldn't say that. Table 1 shows the results of dynamic friction coefficient evaluation performed in the same manner as in Example 4.

Comparative Example 2
Uniform dispersion containing 5% of the same hollow nanosilica particles as in Example 4 with respect to the solid content of polycarbonate polyurethane (hereinafter referred to as binder) (dispersion medium: cyclohexane / acetone / DMF mixed solvent (50/40/10)) Adjusted. This dispersion was applied to the surface of a dark gray napped sheet obtained in the same manner as in Example 4 using a 150 mesh gravure roll (coating amount: 1. the total amount of hollow nanosilica particles and binder). 5 g / m ² ), and drying in a steam dryer at about 110 to 130 ° C., a leather-like sheet having hollow nanosilica particles adhered to the surface was produced.
The obtained leather-like sheet had good grip properties when dry and wet, but it was poor in flexibility, had a harsh feel, and did not have a raised feeling in the first place. It was not a suede leather-like sheet with such a good appearance and touch.

Table 1
Dynamic friction coefficient
When dry When wet
Example 4 2.75 2.92
Example 5
Comparative Example 1 1.61 1.89

Comparative Example 3
A suede-like leather-like sheet was obtained in the same manner as in Example 4 except that hollow nanosilica particles having a primary particle size of 300 μm were adhered on the suede-like leather-like sheet obtained in Example 4. The resulting suede-like leather-like sheet had elegant lighting. The evaluation of the grip property of the sandal produced with this suede-like leather-like sheet was good immediately after the start of the test when dry, but the grip property decreased from the beginning of sweating, and the evaluation was B. The wet evaluation was C.

Comparative Example 4
A suede-like leather-like sheet was obtained in the same manner as in Example 4 except that non-hollow nanosilica particles having a primary particle diameter of 100 μm were adhered on the suede-like leather-like sheet obtained in Example 4. . The resulting suede-like leather-like sheet had elegant lighting. The evaluation of the grip property of the sandal produced with this suede-like leather-like sheet was good immediately after the start of the test when dry, but the grip property decreased from the beginning of sweating, and the evaluation was B. The wet evaluation was C.

Production Example 1
50 parts of polyethylene (sea component) and 50 parts of 6-nylon (island component) were melt-spun in the same melt system to produce sea-island fibers with a fineness of 15 dtex. This sea-island fiber was stretched 2.5 times and crimped, and then cut into a fiber length of 51 mm. The obtained staple was opened with a card and made into a fiber web with a cross wrapper webber. The fiber webs were overlapped, and a fiber entanglement with a basis weight of 320 g / m ² was obtained by needle punching.
13% dimethylformamide (DMF) of polyester-based polyurethane (100% modulus: 100 kg / cm ² ) obtained by copolymerization of polyethylene propylene adipate, 4,4 ″ -diphenylmethane diisocyanate (MDI) and ethylene glycol (EG) ) The resulting fiber entangled body was impregnated. The fiber entangled body impregnated with polyurethane was immersed in a coagulation bath (40 ° C.) of DMF / water = 30/70 for 30 minutes to coagulate the polyurethane in a porous state. Subsequently, after washing with water, the polyethylene in the sea-island fiber is extracted and removed with toluene to convert it into ultrafine fibers having an average fineness of 0.01 dtex, and a thickness of 0.8 mm comprising a fiber bundle of 6-nylon ultrafine fibers and porous polyurethane. A fibrous base material was obtained. The obtained fibrous base material was dyed ocher with a metal-containing dye using a Wins dyeing machine.

Production Example 2
40 parts of thermoplastic polyvinyl alcohol (sea component) and 60 parts of polyethylene terephthalate (island component) are melted with a separate extruder and introduced into a composite spinning nozzle, and the fiber spun from the nozzle is caught while being drawn by the force of airflow. Sea island fiber web was made by spraying on the collection net. The fineness of the fibers constituting the web was 3 dtex. The obtained fiber webs were superposed and made into a fiber entanglement with a basis weight of 400 g / m ² by needle punching. When polyvinyl alcohol was extracted from the fiber entangled body in hot water at 90 ° C., slight shrinkage occurred and a fiber entangled body having a basis weight of 320 g / m ² was obtained.
A water-based emulsion of polyether-based polyurethane (trade name “Evaphanol APC-48” manufactured by Nikka Chemical Co., Ltd.) was impregnated with a solution diluted with water so that the solid content concentration was 5%, and squeezed. . The pickup was 60%. Thereafter, drying was performed to obtain a fibrous base material having a thickness of 0.8 mm made of ultrafine fibers having an average fineness of 0.1 dtex and polyurethane contained therein. The obtained fibrous base material was dyed ocher with a disperse dye using a circular dyeing machine.

Example 6
One side of the fibrous base material obtained in Production Example 1 was raised with # 400 sandpaper to obtain a raised sheet.
On the other hand, a surface obtained by surface-modifying hollow nanosilica particles having a primary particle size of 50 to 150 nm, a silica shell thickness of 5 to 15 nm, and shell wall pores of 2 nm or less (BET method) with an isocyanate group by the method described in Patent Document 7 A uniform MEK dispersion containing 2% modified particles was prepared. This dispersion is applied to the surface of the napped sheet using a 150 mesh gravure roll (coating amount: hollow nanosilica particles 0.2 g / m ² ) and dried in a hot air dryer set at 130 ° C. A napped sheet having nanosilica particles adhered to the napped portion was obtained.

A uniform solution (solvent: cyclohexanone / acetone / DMF mixed solvent (50/40/10)) containing 3% of the same polyester-based polyurethane impregnated in the sheet is placed on the napped sheet, and an elliptical dot pattern A semi-silver-like leather-like sheet having a silver surface portion and a napped portion on the surface was obtained by application using a gravure roll having a major axis of 2 mm and a minor axis of 1 mm.
The obtained semi-silver tone leather-like sheet had a surface silver coverage of 30%, and the napped portion had fine and elegant lighting. The evaluation of grip properties of the sandals produced with this semi-silver-like leather-like sheet was A when dry and wet.

Example 7
One side of the fibrous base material obtained in Production Example 1 was raised with # 400 sandpaper to obtain a raised sheet. On the other hand, a uniform MEK dispersion containing 2% of hollow nanosilica particles having a primary particle size without functional group modification of 50 to 150 nm, a silica shell thickness of 5 to 15 nm and a shell wall pore of 2 nm or less (BET method) was prepared. did. This dispersion is applied to the surface of the napped sheet using a 150 mesh gravure roll (coating amount: hollow nanosilica particles 0.2 g / m ² ) and dried in a hot air dryer set at 130 ° C. A raised sheet having nano silica particles attached to the raised portion was obtained, and then the raised surface was embossed with a basketball-type embossing roll to obtain a raised sheet having a basket-like texture.

Uniform dispersion (dispersion medium: cyclohexanone / cyclohexane) containing the same polyester-based polyurethane used in Example 6 as a binder, containing 10% hollow nanosilica particles, and having a total solid content of 3%. Acetone / DMF mixed solvent (50/40/10)) was applied using a 150 mesh gravure roll to obtain a semi-silver-like leather-like sheet.
The obtained leather-like sheet with a semi-silver tone had a silver surface portion covered with polyurethane only at the embossed portion, and the coverage of the surface silver surface portion was 50%. Napped hair remained in the valley of the grain, and it had lighting. The evaluation of the grip property of the sandal produced with this leather-like sheet with a semi-silver was A when dry and wet.

Example 8
A napped sheet having basketball-like wrinkles in which the hollow nanosilica particles prepared in Example 7 adhered to the napped portion was used. On this napping sheet, the same polyester polyurethane used in Example 6 was used as a binder, and 10% isocyanate-modified hollow nanosilica particles were contained in the binder, and the total solid content was adjusted to 3%. A uniform dispersion (dispersion medium: cyclohexanone / acetone / DMF mixed solvent (50/40/10)) was applied using a 150 mesh gravure roll to obtain a semi-silver-like leather-like sheet.
The obtained semi-silver-like leather-like sheet had a silver surface portion covered with polyurethane only at the embossed portion, and the coverage of the surface silver surface portion was 50%. Napped hair remained in the valley of the grain, and it had lighting. The evaluation of grip properties of the sandals produced with this semi-silver-like leather-like sheet was A when dry and wet.

Example 9
A homogeneous solution containing 3% of the same polyester polyurethane impregnated in the sheet (solvent: cyclohexanone / acetone / DMF mixed solvent (50/40 / 10)) was applied and dried using a 150 mesh gravure roll, and then embossed with an embossing roll simulating the texture of an adult cow. Thereafter, the peak of the grain was brushed with # 600 sandpaper to obtain a semi-silvered napped sheet.

On the other hand, a uniform MEK dispersion containing 2% of the surface-modified particles used in Example 6 was prepared. This dispersion is applied to the surface of the semi-silvered raised sheet using a 150 mesh gravure roll (coating amount: hollow nanosilica particles 0.2 g / m ² ) and dried in a hot air dryer set at 130 ° C. A semi-silver-like leather-like sheet was obtained.
The obtained leather-like sheet had a surface silver coverage of 60%, surface modified particles adhered to both the silver surface and the napped portion, and fine and elegant lighting. The evaluation of the grip property of the sandal produced with this leather-like sheet was A when dry and wet.

Example 10
The same polyester-based polyurethane used in Example 6 is used as a binder on the raised sheet having basket-like wrinkles obtained in Example 8, and contains 10% hollow nanosilica particles with respect to the binder, and the total solid content is 3 % Uniform dispersion liquid (dispersion medium: cyclohexanone / acetone / DMF mixed solvent (50/40/10)) was applied using a 150 mesh gravure roll so that the silver surface portion and the napped portion were A mixed semi-silver leather-like sheet was obtained.
The obtained leather-like sheet had a silver surface portion coated with polyurethane only at the embossed portion, and the coverage of the surface silver surface portion was 50%. Napped hair remained in the valley of the grain, and it had lighting. The evaluation of the grip property of the sandal produced with this leather-like sheet was A when dry and wet.

Example 11
Except for using the fibrous base material obtained in Production Example 2, the same operation as in Example 9 was performed to obtain a semi-silver-like leather-like sheet in which a silver surface portion and a napped portion were mixed.
The obtained leather-like sheet had a coverage of 55% on the surface silver surface portion, and had an elegant lighting. The evaluation of grip properties of sandals produced with a semi-silver leather-like sheet was A for both dry and wet conditions.

Comparative Example 5
In Example 6, a semi-silver-like leather-like sheet was obtained in the same manner as in Example 6 except that the hollow nanosilica particles were not attached to the raised sheet. The obtained semi-silver-like leather-like sheet had a surface coverage of 30% and had elegant lighting. Gripping evaluation of sandals made with this semi-silver-like leather-like sheet was good immediately after the start of the test when dry, but the gripping deteriorated from the beginning of sweating, and the evaluation was B. It was. The wet evaluation was C.

Comparative Example 6
A leather-like sheet was produced in the same manner as in Example 2 until a coating layer was formed on the fibrous base material and its surface, and then a discontinuous recess was formed on the surface of the coating layer.
In the same manner as in Example 2, hollow silica particles having a primary particle size of 300 μm were uniformly dispersed and adjusted and applied to a polycarbonate-based polyurethane dispersion (containing 10% based on the solid content of the (binder)) to form a surface layer.
Using the obtained leather-like sheet as a surface material, a volleyball was produced according to a conventional method. The evaluation of wet grip properties of the obtained volleyball was B.

Comparative Example 7
A leather-like sheet was produced in the same manner as in Example 2 until a coating layer was formed on the fibrous base material and its surface, and then a discontinuous recess was formed on the surface of the coating layer.
Non-hollow silica particles having a primary particle size of 100 nm were uniformly dispersed and adjusted and applied to a polycarbonate-based polyurethane dispersion (containing 10% (solid binder) solid content) in the same manner as in Example 2 to form a surface layer.
Using the obtained leather-like sheet as a surface material, a volleyball was produced according to a conventional method. The evaluation of wet grip properties of the obtained volleyball was B.

Comparative Example 8
A leather-like sheet was produced in the same manner as in Example 2 until a coating layer was formed on the fibrous base material and its surface, and then a discontinuous recess was formed on the surface of the coating layer.
In the same manner as in Example 2, hollow silica particles having a primary particle size of 20 nm were uniformly dispersed and adjusted and applied to a polycarbonate-based polyurethane dispersion (containing 10% of the (binder) solid content) to form a surface layer.
Using the obtained leather-like sheet as a surface material, a volleyball was produced according to a conventional method. The evaluation of wet grip properties of the obtained volleyball was B.

Since the silvered leather-like sheet of the present invention exhibits excellent wet grip properties, applications that require wet grip properties such as game balls, gloves, shoe insoles, seats, or floor materials, It is suitable as a material for shoe soles and various grips.
The suede-like leather-like sheet of the present invention has a fine and elegant natural suede-like or natural nubuck-like appearance with napping, excellent color development, and has a soft, bulging and full texture. On the other hand, it exhibits excellent grip properties whether dry or wet. Golf gloves, batting gloves, horse riding gloves, marine sports gloves, sports gloves such as driving gloves for cars, motorcycles, bicycles, etc., machine tool work gloves, agricultural work gloves, lifesaving work gloves, It can be suitably used for applications such as work gloves such as military gloves, as well as the surface material of the grip part of the racket, the surface material of the buttocks of the riding pants, the surface material of the seat of the vehicle, for clothing, and for shoes. Moreover, the semi-silver-tone leather-like sheet of the present invention of the outer side of sports shoes and sandals, etc., has a semi-silver-like appearance with a dense and elegant lighting effect, and is excellent regardless of whether dry or wet Demonstrate grip. Not only for sports gloves such as golf gloves and batting gloves, but also for work gloves such as machine tool work gloves, sports shoes, sandals tops, tennis rackets and golf club grip surface materials Can be suitably used.

Claims

A leather-like sheet having a fibrous base material and a silver surface portion covering 10% or more of the surface thereof, the silver surface portion comprising a surface layer and a coating layer optionally formed, the surface layer having a primary particle diameter of 50 to 150 nm non-modified hollow nanosilica particles and a polymer elastic body, or a compound comprising a modified hollow nanosilica particle and an arbitrary polymer elastic body, the modified hollow nanosilica particles having an isocyanate group, an alkyl group, an aryl group and a UV functional group A leather-like sheet which is a particle surface-modified with at least one compound selected from
The leather-like sheet according to claim 1, wherein the unmodified and modified hollow nanosilica particles have a silica shell thickness of 5 to 15 nm and shell wall pores of 5 nm or less.
The leather-like sheet according to any one of claims 1 to 2, wherein a surface of the fibrous base material is entirely covered with a silver surface portion.
The fiber base material is exposed at a portion where the silver surface portion does not exist on the surface of the fiber base material, and napped fibers made of fibers constituting the fiber base material are present. A leather-like sheet as described in 1.
The fiber base material according to any one of claims 1 to 4, wherein the fibrous base material includes a fiber entangled body composed of a bundle of ultrafine fibers having an average fineness of 0.0001 to 0.3 dtex and a porous polymer elastic body. Leather-like sheet.
The leather-like sheet according to claim 5, wherein a mass ratio of the ultrafine fibers to the polymer elastic body is 35/65 to 90/10.
The leather-like sheet according to any one of claims 1 to 6, wherein the silver surface portion is nonporous.
The leather-like sheet according to any one of claims 1 to 7, wherein the coating layer contains a polymer elastic body but does not contain unmodified and modified hollow nanosilica particles.
The leather-like sheet according to claim 8, wherein the covering layer is nonporous.
The leather-like sheet according to claim 8, wherein both the covering layer and the surface layer are nonporous.
The leather-like sheet according to claim 8, wherein the covering layer is porous and the surface layer is nonporous.
The leather-like sheet according to any one of claims 1 to 11, wherein a continuous convex portion and a discontinuous concave portion are formed in the silver surface portion.
The leather-like sheet according to any one of claims 1 to 12, wherein the coating layer is formed with continuous convex portions and discontinuous concave portions.
The leather-like sheet according to any one of claims 1 to 13, wherein the abundance of the unmodified hollow nanosilica particles is 0.02 to 0.8 g / m 2 .
The leather-like sheet according to any one of claims 1 to 13, wherein the abundance of the surface-modified hollow nanosilica particles is 0.05 to 1 g / m 2 .
An artificial leather product, wherein at least a part of the surface is formed of the leather-like sheet according to any one of claims 1 to 15.
The artificial leather product according to claim 16, wherein the artificial leather product is a game ball.
The artificial leather product according to claim 17, wherein the game ball is a volleyball.
A fiber entangled body composed of a bundle of ultrafine fibers having an average fineness of 0.3 dtex or less and a fibrous base material composed of a polymer elastic body existing inside the fiber entangled body, and the surface of the fibrous base material A suede-like leather-like sheet having napped fibers, wherein the unmodified or modified hollow nanosilica particles having a primary particle size of 50 to 150 nm are present on at least the napped surface.
The modified hollow nanosilica particle is a particle whose surface is modified with at least one compound selected from a compound having an isocyanate group, a compound having an alkyl group, a compound having an aryl group, and a compound having a UV functional group. 19. Suede-like leather-like sheet according to 19.
The suede-like leather-like sheet according to claim 19 or 20, wherein the unmodified or modified hollow nanosilica particles have a silica shell thickness of 5 to 15 nm and a shell wall pore of 5 nm or less.
The suede-like leather-like sheet according to any one of claims 19 to 22, wherein the abundance of the unmodified or modified hollow nanosilica particles is 0.02 to 0.8 g / m 2 .
The suede-like leather-like sheet according to any one of claims 19 to 22, wherein at least a part of the unmodified or modified hollow nanosilica particles is present so as to cover a part of a napped surface made of ultrafine fibers.
The artificial leather product, wherein at least a part of the surface material is the suede-like leather-like sheet according to any one of claims 19 to 23.
A sports glove or a working glove using the artificial leather product according to claim 24.
Sports shoes or sandals using the artificial leather product according to claim 24.
A leather-like sheet in which a surface of a fibrous base material is a leather-like sheet in which a covering portion and a napped portion made of fibers constituting the fibrous base material are mixed, and the napped portion has an unmodified or modified hollow having a primary particle diameter of 50 to 150 nm. Leather-like sheet with nano silica particles attached.
The modified hollow nanosilica particle is a particle whose surface is modified with at least one compound selected from a compound having an isocyanate group, a compound having an alkyl group, a compound having an aryl group, and a compound having a UV functional group. 27. Leather-like sheet according to 27.
The leather-like sheet according to claim 27 or 28, wherein the unmodified or modified hollow nanosilica particles have a silica shell thickness of 5 to 15 nm and shell wall pores of 5 nm or less.
The leather-like article according to any one of claims 27 to 29, wherein the coating part does not contain unmodified and modified hollow nanosilica particles, and the area ratio of the coating part to the napped part is 10/90 to 60/40. Sheet.
The covering portion is made of a polymer elastic body and unmodified hollow nanosilica particles having a primary particle diameter of 50 to 150 nm, and the area ratio of the covering portion to the napped portion is 10/90 to 90/10 on the surface of the fibrous base material. The leather-like sheet according to any one of claims 27 to 29.
The primary particle size whose surface is modified with at least one compound selected from a compound having a polymer elastic body and an isocyanate group, a compound having an alkyl group, a compound having an aryl group, and a compound having a UV functional group. 30 is a modified hollow nanosilica particle having a diameter of 50 to 150 nm, and the area ratio of the covering portion to the raised portion is 10/90 to 90/10 on the surface of the fibrous base material. The leather-like sheet of description.
At least a part of the surface of the coating portion is primary-modified with at least one compound selected from a compound having an isocyanate group, a compound having an alkyl group, a compound having an aryl group, and a compound having a UV functional group. The modified hollow nanosilica particles having a particle diameter of 50 to 150 nm are present, and the area ratio of the covering portion to the napped portion is 10/90 to 90/10 on the surface of the fibrous base material. The leather-like sheet | seat of Claim 1.
The leather-like sheet according to any one of claims 27 to 34, wherein the fibrous base material is a fiber entangled body composed of fiber bundles of ultrafine fibers having an average fineness of 0.0001 to 0.3 dtex.
35. Any one of claims 27 to 34, wherein the fibrous base material is composed of a fiber entangled body composed of a fiber bundle of ultrafine fibers having an average fineness of 0.0001 to 0.3 dtex, and a polymer elastic body contained therein. Leather-like sheet.
The leather-like sheet according to claim 35, wherein a mass ratio of the ultrafine fibers to the polymer elastic body is 35/65 to 90/10.
An artificial leather product, wherein at least a part of the surface material is the leather-like sheet according to any one of claims 27 to 36.
A sports glove, work glove, sports shoe or sandal using the artificial leather product according to claim 37.